gorethink

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 Go to latest Published: Aug 27, 2015 License: Apache-2.0, MIT Imports: 23 Imported by: 0

README

GoRethink - RethinkDB Driver for Go

GitHub tag GoDoc build status

Go driver for RethinkDB

GoRethink Logo

Current version: v1.0.0 (RethinkDB v2.0)

Please note that this version of the driver only supports versions of RethinkDB using the v0.4 protocol (any versions of the driver older than RethinkDB 2.0 will not work).

Gitter

Installation

go get -u github.com/dancannon/gorethink

Or (pinned to the v1.x.x tag)

go get gopkg.in/dancannon/gorethink.v1

Connection

Basic Connection

Setting up a basic connection with RethinkDB is simple:

import (
    r "github.com/dancannon/gorethink"
)

var session *r.Session

session, err := r.Connect(r.ConnectOpts{
    Address: "localhost:28015",
})
if err != nil {
    log.Fatalln(err.Error())
}

See the documentation for a list of supported arguments to Connect().

Connection Pool

The driver uses a connection pool at all times, by default it creates and frees connections automatically. It's safe for concurrent use by multiple goroutines.

To configure the connection pool MaxIdle, MaxOpen and Timeout can be specified during connection. If you wish to change the value of MaxIdle or MaxOpen during runtime then the functions SetMaxIdleConns and SetMaxOpenConns can be used.

var session *r.Session

session, err := r.Connect(r.ConnectOpts{
    Address: "localhost:28015",
    Database: "test",
    MaxIdle: 10,
    MaxOpen: 10,
})
if err != nil {
    log.Fatalln(err.Error())
}

session.SetMaxOpenConns(5)
Connect to a cluster

To connect to a RethinkDB cluster which has multiple nodes you can use the following syntax. When connecting to a cluster with multiple nodes queries will be distributed between these nodes.

var session *r.Session

session, err := r.Connect(r.ConnectOpts{
    Addresses: []string{"localhost:28015", "localhost:28016"},
    Database: "test",
    AuthKey:  "14daak1cad13dj",
    DiscoverHosts: true,
})
if err != nil {
    log.Fatalln(err.Error())
}

When DiscoverHosts is true any nodes are added to the cluster after the initial connection then the new node will be added to the pool of available nodes used by GoRethink. Unfortunately the canonical address of each server in the cluster MUST be set as otherwise clients will try to connect to the database nodes locally. For more information about how to set a RethinkDB servers canonical address set this page http://www.rethinkdb.com/docs/config-file/.

Query Functions

This library is based on the official drivers so the code on the API page should require very few changes to work.

To view full documentation for the query functions check the API reference or GoDoc

Slice Expr Example

r.Expr([]interface{}{1, 2, 3, 4, 5}).Run(session)

Map Expr Example

r.Expr(map[string]interface{}{"a": 1, "b": 2, "c": 3}).Run(session)

Get Example

r.Db("database").Table("table").Get("GUID").Run(session)

Map Example (Func)

r.Expr([]interface{}{1, 2, 3, 4, 5}).Map(func (row Term) interface{} {
    return row.Add(1)
}).Run(session)

Map Example (Implicit)

r.Expr([]interface{}{1, 2, 3, 4, 5}).Map(r.Row.Add(1)).Run(session)

Between (Optional Args) Example

r.Db("database").Table("table").Between(1, 10, r.BetweenOpts{
    Index: "num",
    RightBound: "closed",
}).Run(session)
Optional Arguments

As shown above in the Between example optional arguments are passed to the function as a struct. Each function that has optional arguments as a related struct. This structs are named in the format FunctionNameOpts, for example BetweenOpts is the related struct for Between.

Results

Different result types are returned depending on what function is used to execute the query.

  • Run returns a cursor which can be used to view all rows returned.
  • RunWrite returns a WriteResponse and should be used for queries such as Insert, Update, etc...
  • Exec sends a query to the server and closes the connection immediately after reading the response from the database. If you do not wish to wait for the response then you can set the NoReply flag.

Example:

res, err := r.Db("database").Table("tablename").Get(key).Run(session)
if err != nil {
    // error
}
defer res.Close() // Always ensure you close the cursor to ensure connections are not leaked

Cursors have a number of methods available for accessing the query results

  • Next retrieves the next document from the result set, blocking if necessary.
  • All retrieves all documents from the result set into the provided slice.
  • One retrieves the first document from the result set.

Examples:

var row interface{}
for res.Next(&row) {
    // Do something with row
}
if res.Err() != nil {
    // error
}

var rows []interface{}
err := res.All(&rows)
if err != nil {
    // error
}

var row interface{}
err := res.One(&row)
if err == r.ErrEmptyResult {
    // row not found
}
if err != nil {
    // error
}

Encoding/Decoding Structs

When passing structs to Expr(And functions that use Expr such as Insert, Update) the structs are encoded into a map before being sent to the server. Each exported field is added to the map unless

  • the field's tag is "-", or
  • the field is empty and its tag specifies the "omitempty" option.

Each fields default name in the map is the field name but can be specified in the struct field's tag value. The "gorethink" key in the struct field's tag value is the key name, followed by an optional comma and options. Examples:

// Field is ignored by this package.
Field int `gorethink:"-"`
// Field appears as key "myName".
Field int `gorethink:"myName"`
// Field appears as key "myName" and
// the field is omitted from the object if its value is empty,
// as defined above.
Field int `gorethink:"myName,omitempty"`
// Field appears as key "Field" (the default), but
// the field is skipped if empty.
// Note the leading comma.
Field int `gorethink:",omitempty"`

NOTE: It is strongly recommended that struct tags are used to explicitly define the mapping between your Go type and how the data is stored by RethinkDB. This is especially important when using an Id field as by default RethinkDB will create a field named id as the primary key (note that the RethinkDB field is lowercase but the Go version starts with a capital letter).

Benchmarks

Everyone wants their project's benchmarks to be speedy. And while we know that rethinkDb and the gorethink driver are quite fast, our primary goal is for our benchmarks to be correct. They are designed to give you, the user, an accurate picture of writes per second (w/s). If you come up with a accurate test that meets this aim, submit a pull request please.

Thanks to @jaredfolkins for the contribution.

Type Value
Model Name MacBook Pro
Model Identifier MacBookPro11,3
Processor Name Intel Core i7
Processor Speed 2.3 GHz
Number of Processors 1
Total Number of Cores 4
L2 Cache (per Core) 256 KB
L3 Cache 6 MB
Memory 16 GB 
BenchmarkBatch200RandomWrites                20                              557227775                     ns/op
BenchmarkBatch200RandomWritesParallel10      30                              354465417                     ns/op
BenchmarkBatch200SoftRandomWritesParallel10  100                             761639276                     ns/op
BenchmarkRandomWrites                        100                             10456580                      ns/op
BenchmarkRandomWritesParallel10              1000                            1614175                       ns/op
BenchmarkRandomSoftWrites                    3000                            589660                        ns/op
BenchmarkRandomSoftWritesParallel10          10000                           247588                        ns/op
BenchmarkSequentialWrites                    50                              24408285                      ns/op
BenchmarkSequentialWritesParallel10          1000                            1755373                       ns/op
BenchmarkSequentialSoftWrites                3000                            631211                        ns/op
BenchmarkSequentialSoftWritesParallel10      10000                           263481                        ns/op

Examples

Many functions have examples and are viewable in the godoc, alternatively view some more full features examples on the wiki.

License

Copyright 2013 Daniel Cannon

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

Donations

Donations

Documentation

Overview

Package gorethink implements a Go driver for RethinkDB

Current version: v1.0.0 (RethinkDB v2.0) For more in depth information on how to use RethinkDB check out the API docs at http://rethinkdb.com/api

Example 
session, err := Connect(ConnectOpts{
	Address: url,
})
if err != nil {
	log.Fatalln(err.Error())
}

res, err := Expr("Hello World").Run(session)
if err != nil {
	log.Fatalln(err.Error())
}

var response string
err = res.One(&response)
if err != nil {
	log.Fatalln(err.Error())
}

fmt.Println(response)

Output:

Hello World

Index

Examples

Constants

This section is empty.

Variables

View Source 
var (
	// ErrNoHosts is returned when no hosts to the Connect method.
	ErrNoHosts = errors.New("no hosts provided")
	// ErrNoConnectionsStarted is returned when the driver couldn't to any of
	// the provided hosts.
	ErrNoConnectionsStarted = errors.New("no connections were made when creating the session")
	// ErrInvalidNode is returned when attempting to connect to a node which
	// returns an invalid response.
	ErrInvalidNode = errors.New("invalid node")
	// ErrClusterClosed is returned when a query is executed after the connection
	// to the cluster has been closed.
	ErrClusterClosed = errors.New("cluster closed")
	// ErrNoConnections is returned when there are no active connections in the
	// clusters connection pool.
	ErrNoConnections = errors.New("gorethink: no connections were available")
	// ErrConnectionClosed is returned when trying to send a query with a closed
	// connection.
	ErrConnectionClosed = errors.New("gorethink: the connection is closed")
)
View Source 
var (
	// MinVal represents the smallest possible value RethinkDB can store
	MinVal = constructRootTerm("MinVal", p.Term_MINVAL, []interface{}{}, map[string]interface{}{})
	// MaxVal represents the smallest possible value RethinkDB can store
	MaxVal = constructRootTerm("MaxVal", p.Term_MAXVAL, []interface{}{}, map[string]interface{}{})
)
View Source 
var (

	// Monday is a constant representing the day of the week Monday
	Monday = constructRootTerm("Monday", p.Term_MONDAY, []interface{}{}, map[string]interface{}{})
	// Tuesday is a constant representing the day of the week Tuesday
	Tuesday = constructRootTerm("Tuesday", p.Term_TUESDAY, []interface{}{}, map[string]interface{}{})
	// Wednesday is a constant representing the day of the week Wednesday
	Wednesday = constructRootTerm("Wednesday", p.Term_WEDNESDAY, []interface{}{}, map[string]interface{}{})
	// Thursday is a constant representing the day of the week Thursday
	Thursday = constructRootTerm("Thursday", p.Term_THURSDAY, []interface{}{}, map[string]interface{}{})
	// Friday is a constant representing the day of the week Friday
	Friday = constructRootTerm("Friday", p.Term_FRIDAY, []interface{}{}, map[string]interface{}{})
	// Saturday is a constant representing the day of the week Saturday
	Saturday = constructRootTerm("Saturday", p.Term_SATURDAY, []interface{}{}, map[string]interface{}{})
	// Sunday is a constant representing the day of the week Sunday
	Sunday = constructRootTerm("Sunday", p.Term_SUNDAY, []interface{}{}, map[string]interface{}{})

	// January is a constant representing the month January
	January = constructRootTerm("January", p.Term_JANUARY, []interface{}{}, map[string]interface{}{})
	// February is a constant representing the month February
	February = constructRootTerm("February", p.Term_FEBRUARY, []interface{}{}, map[string]interface{}{})
	// March is a constant representing the month March
	March = constructRootTerm("March", p.Term_MARCH, []interface{}{}, map[string]interface{}{})
	// April is a constant representing the month April
	April = constructRootTerm("April", p.Term_APRIL, []interface{}{}, map[string]interface{}{})
	// May is a constant representing the month May
	May = constructRootTerm("May", p.Term_MAY, []interface{}{}, map[string]interface{}{})
	// June is a constant representing the month June
	June = constructRootTerm("June", p.Term_JUNE, []interface{}{}, map[string]interface{}{})
	// July is a constant representing the month July
	July = constructRootTerm("July", p.Term_JULY, []interface{}{}, map[string]interface{}{})
	// August is a constant representing the month August
	August = constructRootTerm("August", p.Term_AUGUST, []interface{}{}, map[string]interface{}{})
	// September is a constant representing the month September
	September = constructRootTerm("September", p.Term_SEPTEMBER, []interface{}{}, map[string]interface{}{})
	// October is a constant representing the month October
	October = constructRootTerm("October", p.Term_OCTOBER, []interface{}{}, map[string]interface{}{})
	// November is a constant representing the month November
	November = constructRootTerm("November", p.Term_NOVEMBER, []interface{}{}, map[string]interface{}{})
	// December is a constant representing the month December
	December = constructRootTerm("December", p.Term_DECEMBER, []interface{}{}, map[string]interface{}{})
)
View Source 
var ErrBadConn = errors.New("gorethink: bad connection")

ErrBadConn should be returned by a connection operation to signal to the pool that a driver.Conn is in a bad state (such as the server having earlier closed the connection) and the pool should retry on a new connection.

To prevent duplicate operations, ErrBadConn should NOT be returned if there's a possibility that the database server might have performed the operation. Even if the server sends back an error, you shouldn't return ErrBadConn.

View Source 
var ErrEmptyResult = errors.New("The result does not contain any more rows")

Error constants

View Source 
var Row = constructRootTerm("Doc", p.Term_IMPLICIT_VAR, []interface{}{}, map[string]interface{}{})

Row returns the currently visited document. Note that Row does not work within subqueries to access nested documents; you should use anonymous functions to access those documents instead. Also note that unlike in other drivers to access a rows fields you should call Field. For example: 

r.row("fieldname") should instead be r.Row.Field("fieldname")

Functions

func SetVerbose 

func SetVerbose(verbose bool)

SetVerbose allows the driver logging level to be set. If true is passed then the log level is set to Debug otherwise it defaults to Info.

Types

type BetweenOpts 

type BetweenOpts struct {
	Index      interface{} `gorethink:"index,omitempty"`
	LeftBound  interface{} `gorethink:"left_bound,omitempty"`
	RightBound interface{} `gorethink:"right_bound,omitempty"`
}

BetweenOpts contains the optional arguments for the Between term

type ChangeResponse 

type ChangeResponse struct {
	NewValue interface{} `gorethink:"new_val"`
	OldValue interface{} `gorethink:"old_val"`
}

ChangeResponse is a helper type used when dealing with changefeeds. The type contains both the value before the query and the new value.

type ChangesOpts 

type ChangesOpts struct {
	Squash        interface{} `gorethink:"squash,omitempty"`
	IncludeStates interface{} `gorethink:"include_states,omitempty"`
}

ChangesOpts contains the optional arguments for the Changes term

type CircleOpts 

type CircleOpts struct {
	NumVertices interface{} `gorethink:"num_vertices,omitempty"`
	GeoSystem   interface{} `gorethink:"geo_system,omitempty"`
	Unit        interface{} `gorethink:"unit,omitempty"`
	Fill        interface{} `gorethink:"fill,omitempty"`
}

CircleOpts contains the optional arguments for the Circle term.

type CloseOpts 

type CloseOpts struct {
	NoReplyWait bool `gorethink:"noreplyWait,omitempty"`
}

CloseOpts allows calls to the Close function to be configured.

type Cluster 

type Cluster struct {
	// contains filtered or unexported fields
}

A Cluster represents a connection to a RethinkDB cluster, a cluster is created by the Session and should rarely be created manually.

The cluster keeps track of all nodes in the cluster and if requested can listen for cluster changes and start tracking a new node if one appears. Currently nodes are removed from the pool if they become unhealthy (100 failed queries). This should hopefully soon be replaced by a backoff system.

func NewCluster 

func NewCluster(hosts []Host, opts *ConnectOpts) (*Cluster, error)

NewCluster creates a new cluster by connecting to the given hosts.

func (*Cluster) AddSeeds 

func (c *Cluster) AddSeeds(hosts []Host)

AddSeeds adds new seed hosts to the cluster.

func (*Cluster) Close 

func (c *Cluster) Close(optArgs ...CloseOpts) error

Close closes the cluster

func (*Cluster) Exec 

func (c *Cluster) Exec(q Query) (err error)

Exec executes a ReQL query using the cluster to connect to the database

func (*Cluster) GetHealthyNodes 

func (c *Cluster) GetHealthyNodes() []*Node

GetHealthyNodes returns a list of all healthy nodes in the cluster

func (*Cluster) GetNodes 

func (c *Cluster) GetNodes() []*Node

GetNodes returns a list of all nodes in the cluster

func (*Cluster) GetRandomNode 

func (c *Cluster) GetRandomNode() (*Node, error)

GetRandomNode returns a random node on the cluster TODO(dancannon) replace with hostpool

func (*Cluster) IsConnected 

func (c *Cluster) IsConnected() bool

IsConnected returns true if cluster has nodes and is not already closed.

func (*Cluster) Query 

func (c *Cluster) Query(q Query) (cursor *Cursor, err error)

Query executes a ReQL query using the cluster to connect to the database

func (*Cluster) SetMaxIdleConns 

func (c *Cluster) SetMaxIdleConns(n int)

SetMaxIdleConns sets the maximum number of connections in the idle connection pool.

func (*Cluster) SetMaxOpenConns 

func (c *Cluster) SetMaxOpenConns(n int)

SetMaxOpenConns sets the maximum number of open connections to the database.

type ConnectOpts 

type ConnectOpts struct {
	Address   string        `gorethink:"address,omitempty"`
	Addresses []string      `gorethink:"addresses,omitempty"`
	Database  string        `gorethink:"database,omitempty"`
	AuthKey   string        `gorethink:"authkey,omitempty"`
	Timeout   time.Duration `gorethink:"timeout,omitempty"`
	TLSConfig *tls.Config   `gorethink:"tlsconfig,omitempty"`

	MaxIdle int `gorethink:"max_idle,omitempty"`
	MaxOpen int `gorethink:"max_open,omitempty"`

	// DiscoverHosts is used to enable host discovery, when true the driver
	// will attempt to discover any new nodes added to the cluster and then
	// start sending queries to these new nodes.
	DiscoverHosts bool `gorethink:"discover_hosts,omitempty"`
	// NodeRefreshInterval is used to determine how often the driver should
	// refresh the status of a node.
	NodeRefreshInterval time.Duration `gorethink:"node_refresh_interval,omitempty"`
}

ConnectOpts is used to specify optional arguments when connecting to a cluster.

type Connection 

type Connection struct {
	// contains filtered or unexported fields
}

Connection is a connection to a rethinkdb database. Connection is not thread safe and should only be accessed be a single goroutine

func NewConnection 

func NewConnection(address string, opts *ConnectOpts) (*Connection, error)

NewConnection creates a new connection to the database server

func (*Connection) Close 

func (c *Connection) Close() error

Close closes the underlying net.Conn

func (*Connection) Query 

func (c *Connection) Query(q Query) (*Response, *Cursor, error)

Query sends a Query to the database, returning both the raw Response and a Cursor which should be used to view the query's response.

This function is used internally by Run which should be used for most queries.

type Cursor 

type Cursor struct {
	// contains filtered or unexported fields
}

Cursor is the result of a query. Its cursor starts before the first row of the result set. A Cursor is not thread safe and should only be accessed by a single goroutine at any given time. Use Next to advance through the rows: 

cursor, err := query.Run(session)
...
defer cursor.Close()

var response interface{}
for cursor.Next(&response) {
    ...
}
err = cursor.Err() // get any error encountered during iteration
...

func (*Cursor) All 

func (c *Cursor) All(result interface{}) error

All retrieves all documents from the result set into the provided slice and closes the cursor.

The result argument must necessarily be the address for a slice. The slice may be nil or previously allocated.

Also note that you are able to reuse the same variable multiple times as `All` zeroes the value before scanning in the result. It also attempts to reuse the existing slice without allocating any more space by either resizing or returning a selection of the slice if necessary.

func (*Cursor) Close 

func (c *Cursor) Close() error

Close closes the cursor, preventing further enumeration. If the end is encountered, the cursor is closed automatically. Close is idempotent.

func (*Cursor) Err 

func (c *Cursor) Err() error

Err returns nil if no errors happened during iteration, or the actual error otherwise.

func (*Cursor) IsNil 

func (c *Cursor) IsNil() bool

IsNil tests if the current row is nil.

func (*Cursor) Listen 

func (c *Cursor) Listen(channel interface{})

Listen listens for rows from the database and sends the result onto the given channel. The type that the row is scanned into is determined by the element type of the channel.

Also note that this function returns immediately. 

cursor, err := r.Expr([]int{1,2,3}).Run(session)
if err != nil {
    panic(err)
}

ch := make(chan int)
cursor.Listen(ch)
<- ch // 1
<- ch // 2
<- ch // 3

func (*Cursor) Next 

func (c *Cursor) Next(dest interface{}) bool

Next retrieves the next document from the result set, blocking if necessary. This method will also automatically retrieve another batch of documents from the server when the current one is exhausted, or before that in background if possible.

Next returns true if a document was successfully unmarshalled onto result, and false at the end of the result set or if an error happened. When Next returns false, the Err method should be called to verify if there was an error during iteration.

Also note that you are able to reuse the same variable multiple times as `Next` zeroes the value before scanning in the result.

func (*Cursor) One 

func (c *Cursor) One(result interface{}) error

One retrieves a single document from the result set into the provided slice and closes the cursor.

Also note that you are able to reuse the same variable multiple times as `One` zeroes the value before scanning in the result.

func (*Cursor) Profile 

func (c *Cursor) Profile() interface{}

Profile returns the information returned from the query profiler.

func (*Cursor) Type 

func (c *Cursor) Type() string

Type returns the cursor type (by default "Cursor")

type DeleteOpts 

type DeleteOpts struct {
	Durability    interface{} `gorethink:"durability,omitempty"`
	ReturnChanges interface{} `gorethink:"return_changes,omitempty"`
}

DeleteOpts contains the optional arguments for the Delete term

type DistanceOpts 

type DistanceOpts struct {
	GeoSystem interface{} `gorethink:"geo_system,omitempty"`
	Unit      interface{} `gorethink:"unit,omitempty"`
}

DistanceOpts contains the optional arguments for the Distance term.

type DistinctOpts 

type DistinctOpts struct {
	Index interface{} `gorethink:"index,omitempty"`
}

DistinctOpts contains the optional arguments for the Distinct term

type DuringOpts 

type DuringOpts struct {
	LeftBound  interface{} `gorethink:"left_bound,omitempty"`
	RightBound interface{} `gorethink:"right_bound,omitempty"`
}

DuringOpts contains the optional arguments for the During term

type EqJoinOpts 

type EqJoinOpts struct {
	Index interface{} `gorethink:"index,omitempty"`
}

EqJoinOpts contains the optional arguments for the EqJoin term.

type ExecOpts 

type ExecOpts struct {
	Db             interface{} `gorethink:"db,omitempty"`
	Profile        interface{} `gorethink:"profile,omitempty"`
	UseOutdated    interface{} `gorethink:"use_outdated,omitempty"`
	ArrayLimit     interface{} `gorethink:"array_limit,omitempty"`
	TimeFormat     interface{} `gorethink:"time_format,omitempty"`
	GroupFormat    interface{} `gorethink:"group_format,omitempty"`
	BinaryFormat   interface{} `gorethink:"binary_format,omitempty"`
	GeometryFormat interface{} `gorethink:"geometry_format,omitempty"`

	MinBatchRows              interface{} `gorethink:"min_batch_rows,omitempty"`
	MaxBatchRows              interface{} `gorethink:"max_batch_rows,omitempty"`
	MaxBatchBytes             interface{} `gorethink:"max_batch_bytes,omitempty"`
	MaxBatchSeconds           interface{} `gorethink:"max_batch_seconds,omitempty"`
	FirstBatchScaledownFactor interface{} `gorethink:"first_batch_scaledown_factor,omitempty"`

	NoReply interface{} `gorethink:"noreply,omitempty"`
}

ExecOpts contains the optional arguments for the Exec function and inherits its options from RunOpts, the only difference is the addition of the NoReply field.

When NoReply is true it causes the driver not to wait to receive the result and return immediately.

type FilterOpts 

type FilterOpts struct {
	Default interface{} `gorethink:"default,omitempty"`
}

FilterOpts contains the optional arguments for the Filter term

type GetIntersectingOpts 

type GetIntersectingOpts struct {
	Index interface{} `gorethink:"index,omitempty"`
}

GetIntersectingOpts contains the optional arguments for the GetIntersecting term.

type GetNearestOpts 

type GetNearestOpts struct {
	Index      interface{} `gorethink:"index,omitempty"`
	MaxResults interface{} `gorethink:"max_results,omitempty"`
	MaxDist    interface{} `gorethink:"max_dist,omitempty"`
	Unit       interface{} `gorethink:"unit,omitempty"`
	GeoSystem  interface{} `gorethink:"geo_system,omitempty"`
}

GetNearestOpts contains the optional arguments for the GetNearest term.

type HTTPOpts 

type HTTPOpts struct {
	// General Options
	Timeout      interface{} `gorethink:"timeout,omitempty"`
	Reattempts   interface{} `gorethink:"reattempts,omitempty"`
	Redirects    interface{} `gorethink:"redirect,omitempty"`
	Verify       interface{} `gorethink:"verify,omitempty"`
	ResultFormat interface{} `gorethink:"resul_format,omitempty"`

	// Request Options
	Method interface{} `gorethink:"method,omitempty"`
	Auth   interface{} `gorethink:"auth,omitempty"`
	Params interface{} `gorethink:"params,omitempty"`
	Header interface{} `gorethink:"header,omitempty"`
	Data   interface{} `gorethink:"data,omitempty"`

	// Pagination
	Page      interface{} `gorethink:"page,omitempty"`
	PageLimit interface{} `gorethink:"page_limit,omitempty"`
}

HTTPOpts contains the optional arguments for the HTTP term

type Host 

type Host struct {
	Name string
	Port int
}

Host name and port of server

func NewHost 

func NewHost(name string, port int) Host

NewHost create a new Host

func (Host) String 

func (h Host) String() string

Returns host address (name:port)

type ISO8601Opts 

type ISO8601Opts struct {
	DefaultTimezone interface{} `gorethink:"default_timezone,omitempty"`
}

ISO8601Opts contains the optional arguments for the ISO8601 term

type IndexCreateOpts 

type IndexCreateOpts struct {
	Multi interface{} `gorethink:"multi,omitempty"`
	Geo   interface{} `gorethink:"geo,omitempty"`
}

IndexCreateOpts contains the optional arguments for the IndexCreate term

type IndexRenameOpts 

type IndexRenameOpts struct {
	Overwrite interface{} `gorethink:"overwrite,omitempty"`
}

IndexRenameOpts contains the optional arguments for the IndexRename term

type InsertOpts 

type InsertOpts struct {
	Durability    interface{} `gorethink:"durability,omitempty"`
	ReturnChanges interface{} `gorethink:"return_changes,omitempty"`
	Conflict      interface{} `gorethink:"conflict,omitempty"`
}

InsertOpts contains the optional arguments for the Insert term

type Node 

type Node struct {
	ID   string
	Host Host
	// contains filtered or unexported fields
}

Node represents a database server in the cluster

func (*Node) Close 

func (n *Node) Close(optArgs ...CloseOpts) error

Close closes the session

func (*Node) Closed 

func (n *Node) Closed() bool

Closed returns true if the node is closed

func (*Node) DecrementHealth 

func (n *Node) DecrementHealth()

DecrementHealth decreases the nodes health by 1 (the nodes health starts at maxNodeHealth)

func (*Node) Exec 

func (n *Node) Exec(q Query) (err error)

Exec executes a ReQL query using this nodes connection pool.

func (*Node) IsHealthy 

func (n *Node) IsHealthy() bool

IsHealthy checks the nodes health by ensuring that the health counter is above 0.

func (*Node) NoReplyWait 

func (n *Node) NoReplyWait() error

NoReplyWait ensures that previous queries with the noreply flag have been processed by the server. Note that this guarantee only applies to queries run on the given connection

func (*Node) Query 

func (n *Node) Query(q Query) (cursor *Cursor, err error)

Query executes a ReQL query using this nodes connection pool.

func (*Node) Refresh 

func (n *Node) Refresh()

Refresh attempts to connect to the node and check that it is still connected to the cluster.

If an error occurred or the node is no longer connected then the nodes health is decrease, if there were no issues then the node is marked as being healthy.

func (*Node) ResetHealth 

func (n *Node) ResetHealth()

ResetHealth sets the nodes health back to maxNodeHealth (fully healthy)

func (*Node) SetMaxIdleConns 

func (n *Node) SetMaxIdleConns(idleConns int)

SetMaxIdleConns sets the maximum number of connections in the idle connection pool.

func (*Node) SetMaxOpenConns 

func (n *Node) SetMaxOpenConns(openConns int)

SetMaxOpenConns sets the maximum number of open connections to the database.

type OptArgs 

type OptArgs interface {
	// contains filtered or unexported methods
}

OptArgs is an interface used to represent a terms optional arguments. All optional argument types have a toMap function, the returned map can be encoded and sent as part of the query.

type OrderByOpts 

type OrderByOpts struct {
	Index interface{} `gorethink:"index,omitempty"`
}

OrderByOpts contains the optional arguments for the OrderBy term

type Pool 

type Pool struct {
	// contains filtered or unexported fields
}

A Pool is used to store a pool of connections to a single RethinkDB server

func NewPool 

func NewPool(host Host, opts *ConnectOpts) (*Pool, error)

NewPool creates a new connection pool for the given host

func (*Pool) Close 

func (p *Pool) Close() error

Close closes the database, releasing any open resources.

It is rare to Close a Pool, as the Pool handle is meant to be long-lived and shared between many goroutines.

func (*Pool) Exec 

func (p *Pool) Exec(q Query) error

Exec executes a query without waiting for any response.

func (*Pool) Ping 

func (p *Pool) Ping() error

Ping verifies a connection to the database is still alive, establishing a connection if necessary.

func (*Pool) Query 

func (p *Pool) Query(q Query) (*Cursor, error)

Query executes a query and waits for the response

func (*Pool) SetMaxIdleConns 

func (p *Pool) SetMaxIdleConns(n int)

SetMaxIdleConns sets the maximum number of connections in the idle connection pool.

If MaxOpenConns is greater than 0 but less than the new MaxIdleConns then the new MaxIdleConns will be reduced to match the MaxOpenConns limit

If n <= 0, no idle connections are retained.

func (*Pool) SetMaxOpenConns 

func (p *Pool) SetMaxOpenConns(n int)

SetMaxOpenConns sets the maximum number of open connections to the database.

If MaxIdleConns is greater than 0 and the new MaxOpenConns is less than MaxIdleConns, then MaxIdleConns will be reduced to match the new MaxOpenConns limit

If n <= 0, then there is no limit on the number of open connections. The default is 0 (unlimited).

type Query 

type Query struct {
	Type  p.Query_QueryType
	Token int64
	Term  *Term
	Opts  map[string]interface{}
}

A Query represents a query ready to be sent to the database, A Query differs from a Term as it contains both a query type and token. These values are used by the database to determine if the query is continuing a previous request and also allows the driver to identify the response as they can come out of order.

type RQLClientError 

type RQLClientError struct {
	// contains filtered or unexported fields
}

RQLClientError represents a client error returned from the database.

func (RQLClientError) Error 

func (e RQLClientError) Error() string

func (RQLClientError) String 

func (e RQLClientError) String() string

type RQLCompileError 

type RQLCompileError struct {
	// contains filtered or unexported fields
}

RQLCompileError represents an error that occurs when compiling a query on the database server.

func (RQLCompileError) Error 

func (e RQLCompileError) Error() string

func (RQLCompileError) String 

func (e RQLCompileError) String() string

type RQLConnectionError 

type RQLConnectionError struct {
	// contains filtered or unexported fields
}

RQLConnectionError represents an error when communicating with the database server.

func (RQLConnectionError) Error 

func (e RQLConnectionError) Error() string

func (RQLConnectionError) String 

func (e RQLConnectionError) String() string

type RQLDriverError 

type RQLDriverError struct {
	// contains filtered or unexported fields
}

RQLDriverError represents an unexpected error with the driver, if this error persists please create an issue.

func (RQLDriverError) Error 

func (e RQLDriverError) Error() string

func (RQLDriverError) String 

func (e RQLDriverError) String() string

type RQLRuntimeError 

type RQLRuntimeError struct {
	// contains filtered or unexported fields
}

RQLRuntimeError represents an error when executing an error on the database server, this is also returned by the database when using the `Error` term.

func (RQLRuntimeError) Error 

func (e RQLRuntimeError) Error() string

func (RQLRuntimeError) String 

func (e RQLRuntimeError) String() string

type RandomOpts 

type RandomOpts struct {
	Float interface{} `gorethink:"float,omitempty"`
}

RandomOpts contains the optional arguments for the Random term.

type ReconfigureOpts 

type ReconfigureOpts struct {
	Shards     interface{} `gorethink:"shards,omitempty"`
	Replicas   interface{} `gorethink:"replicas,omitempty"`
	PrimaryTag interface{} `gorethink:"primary_replicas_tag,omitempty"`
	DryRun     interface{} `gorethink:"dry_run,omitempty"`
}

ReconfigureOpts contains the optional arguments for the Reconfigure term.

type ReplaceOpts 

type ReplaceOpts struct {
	Durability    interface{} `gorethink:"durability,omitempty"`
	ReturnChanges interface{} `gorethink:"return_changes,omitempty"`
	NotAtomic     interface{} `gorethink:"non_atomic,omitempty"`
}

ReplaceOpts contains the optional arguments for the Replace term

type Response 

type Response struct {
	Token     int64
	Type      p.Response_ResponseType   `json:"t"`
	Notes     []p.Response_ResponseNote `json:"n"`
	Responses []json.RawMessage         `json:"r"`
	Backtrace []interface{}             `json:"b"`
	Profile   interface{}               `json:"p"`
}

Response represents the raw response from a query, most of the time you should instead use a Cursor when reading from the database.

type RunOpts 

type RunOpts struct {
	Db             interface{} `gorethink:"db,omitempty"`
	Profile        interface{} `gorethink:"profile,omitempty"`
	UseOutdated    interface{} `gorethink:"use_outdated,omitempty"`
	ArrayLimit     interface{} `gorethink:"array_limit,omitempty"`
	TimeFormat     interface{} `gorethink:"time_format,omitempty"`
	GroupFormat    interface{} `gorethink:"group_format,omitempty"`
	BinaryFormat   interface{} `gorethink:"binary_format,omitempty"`
	GeometryFormat interface{} `gorethink:"geometry_format,omitempty"`

	MinBatchRows              interface{} `gorethink:"min_batch_rows,omitempty"`
	MaxBatchRows              interface{} `gorethink:"max_batch_rows,omitempty"`
	MaxBatchBytes             interface{} `gorethink:"max_batch_bytes,omitempty"`
	MaxBatchSeconds           interface{} `gorethink:"max_batch_seconds,omitempty"`
	FirstBatchScaledownFactor interface{} `gorethink:"first_batch_scaledown_factor,omitempty"`
}

RunOpts contains the optional arguments for the Run function.

type Session 

type Session struct {
	// contains filtered or unexported fields
}

A Session represents a connection to a RethinkDB cluster and should be used when executing queries.

func Connect 

func Connect(opts ConnectOpts) (*Session, error)

Connect creates a new database session. To view the available connection options see ConnectOpts.

By default maxIdle and maxOpen are set to 1: passing values greater than the default (e.g. MaxIdle: "10", MaxOpen: "20") will provide a pool of re-usable connections.

Basic connection example: 

session, err := r.Connect(r.ConnectOpts{
	Host: "localhost:28015",
	Database: "test",
	AuthKey:  "14daak1cad13dj",
})

Cluster connection example: 

session, err := r.Connect(r.ConnectOpts{
	Hosts: []string{"localhost:28015", "localhost:28016"},
	Database: "test",
	AuthKey:  "14daak1cad13dj",
})

func (*Session) Close 

func (s *Session) Close(optArgs ...CloseOpts) error

Close closes the session

func (*Session) Exec 

func (s *Session) Exec(q Query) error

Exec executes a ReQL query using the session to connect to the database

func (*Session) NoReplyWait 

func (s *Session) NoReplyWait() error

NoReplyWait ensures that previous queries with the noreply flag have been processed by the server. Note that this guarantee only applies to queries run on the given connection

func (*Session) Query 

func (s *Session) Query(q Query) (*Cursor, error)

Query executes a ReQL query using the session to connect to the database

func (*Session) Reconnect 

func (s *Session) Reconnect(optArgs ...CloseOpts) error

Reconnect closes and re-opens a session.

func (*Session) SetHosts 

func (s *Session) SetHosts(hosts []Host)

SetHosts resets the hosts used when connecting to the RethinkDB cluster

func (*Session) SetMaxIdleConns 

func (s *Session) SetMaxIdleConns(n int)

SetMaxIdleConns sets the maximum number of connections in the idle connection pool.

func (*Session) SetMaxOpenConns 

func (s *Session) SetMaxOpenConns(n int)

SetMaxOpenConns sets the maximum number of open connections to the database.

func (*Session) Use 

func (s *Session) Use(database string)

Use changes the default database used

type SliceOpts 

type SliceOpts struct {
	LeftBound  interface{} `gorethink:"left_bound,omitempty"`
	RightBound interface{} `gorethink:"right_bound,omitempty"`
}

SliceOpts contains the optional arguments for the Slice term

type TableCreateOpts 

type TableCreateOpts struct {
	PrimaryKey        interface{} `gorethink:"primary_key,omitempty"`
	Durability        interface{} `gorethink:"durability,omitempty"`
	Shards            interface{} `gorethink:"shards,omitempty"`
	DataCenter        interface{} `gorethink:"replicas,omitempty"`
	PrimaryReplicaTag interface{} `gorethink:"primary_replica_tag,omitempty"`
}

TableCreateOpts contains the optional arguments for the TableCreate term

type TableOpts 

type TableOpts struct {
	UseOutdated      interface{} `gorethink:"use_outdated,omitempty"`
	IdentifierFormat interface{} `gorethink:"identifier_format,omitempty"`
}

TableOpts contains the optional arguments for the Table term

type Term 

type Term struct {
	// contains filtered or unexported fields
}

A Term represents a query that is being built. Terms consist of a an array of "sub-terms" and a term type. When a Term is a sub-term the first element of the terms data is its parent Term.

When built the term becomes a JSON array, for more information on the format see http://rethinkdb.com/docs/writing-drivers/.

func Add 

func Add(args ...interface{}) Term

Add sums two numbers or concatenates two arrays.

func And 

func And(args ...interface{}) Term

And performs a logical and on two values.

func Args 

func Args(args ...interface{}) Term

Args is a special term usd to splice an array of arguments into another term. This is useful when you want to call a varadic term such as GetAll with a set of arguments provided at runtime.

func Asc 

func Asc(args ...interface{}) Term

Asc is used by the OrderBy term to specify that the ordering be ascending (the default).

func Binary 

func Binary(data interface{}) Term

Binary encapsulates binary data within a query.

The type of data binary accepts depends on the client language. In Go, it expects either a byte array/slice or a bytes.Buffer.

Only a limited subset of ReQL commands may be chained after binary:

  • coerceTo can coerce binary objects to string types
  • count will return the number of bytes in the object
  • slice will treat bytes like array indexes (i.e., slice(10,20) will return bytes 10–19)
  • typeOf returns PTYPE<BINARY>
  • info will return information on a binary object.

func Branch 

func Branch(args ...interface{}) Term

Branch evaluates one of two control paths based on the value of an expression. branch is effectively an if renamed due to language constraints.

The type of the result is determined by the type of the branch that gets executed.

Example

Return heroes and superheroes. 

cur, err := DB("examples").Table("marvel").OrderBy("name").Map(Branch(
	Row.Field("victories").Gt(100),
	Row.Field("name").Add(" is a superhero"),
	Row.Field("name").Add(" is a hero"),
)).Run(session)
if err != nil {
	fmt.Print(err)
	return
}

var strs []string
err = cur.All(&strs)
if err != nil {
	fmt.Print(err)
	return
}

for _, str := range strs {
	fmt.Println(str)
}

Output:

Iron Man is a superhero
Jubilee is a hero

func Circle 

func Circle(point, radius interface{}, optArgs ...CircleOpts) Term

Circle constructs a circular line or polygon. A circle in RethinkDB is a polygon or line approximating a circle of a given radius around a given center, consisting of a specified number of vertices (default 32).

func DB 

func DB(args ...interface{}) Term

DB references a database.

func DBCreate 

func DBCreate(args ...interface{}) Term

DBCreate creates a database. A RethinkDB database is a collection of tables, similar to relational databases.

Note: that you can only use alphanumeric characters and underscores for the database name.

Example

Create a database named ’superheroes’. 

resp, err := DBCreate("superheroes").RunWrite(session)
if err != nil {
	fmt.Print(err)
}

fmt.Printf("%d DB created", resp.DBsCreated)

Output:

1 DB created

func DBDrop 

func DBDrop(args ...interface{}) Term

DBDrop drops a database. The database, all its tables, and corresponding data will be deleted.

Example

Drop a database named ‘superheroes’. 

// Setup database + tables
DBCreate("superheroes").Exec(session)
DB("superheroes").TableCreate("superheroes").Exec(session)
DB("superheroes").TableCreate("battles").Exec(session)

resp, err := DBDrop("superheroes").RunWrite(session)
if err != nil {
	fmt.Print(err)
}

fmt.Printf("%d DB dropped, %d tables dropped", resp.DBsDropped, resp.TablesDropped)

Output:

1 DB dropped, 2 tables dropped

func DBList 

func DBList(args ...interface{}) Term

DBList lists all database names in the system.

func Desc 

func Desc(args ...interface{}) Term

Desc is used by the OrderBy term to specify the ordering to be descending.

func Distance 

func Distance(point1, point2 interface{}, optArgs ...DistanceOpts) Term

Distance calculates the Haversine distance between two points. At least one of the geometry objects specified must be a point.

func Div 

func Div(args ...interface{}) Term

Div divides two numbers.

func Do 

func Do(args ...interface{}) Term

Do evaluates the expr in the context of one or more value bindings. The type of the result is the type of the value returned from expr.

func EpochTime 

func EpochTime(args ...interface{}) Term

EpochTime returns a time object based on seconds since epoch

func Eq 

func Eq(args ...interface{}) Term

Eq returns true if two values are equal.

func Error 

func Error(args ...interface{}) Term

Error throws a runtime error. If called with no arguments inside the second argument to `default`, re-throw the current error.

Example

Return an error 

err := Error("this is a runtime error").Exec(session)
fmt.Println(err)

Output:

func Expr 

func Expr(val interface{}) Term

Expr converts any value to an expression and is also used by many other terms such as Insert and Update. This function can convert the following basic Go types (bool, int, uint, string, float) and even pointers, maps and structs.

When evaluating structs they are encoded into a map before being sent to the server. Each exported field is added to the map unless

  • the field's tag is "-", or
  • the field is empty and its tag specifies the "omitempty" option.

Each fields default name in the map is the field name but can be specified in the struct field's tag value. The "gorethink" key in the struct field's tag value is the key name, followed by an optional comma and options. Examples: 

// Field is ignored by this package.
Field int `gorethink:"-"`
// Field appears as key "myName".
Field int `gorethink:"myName"`
// Field appears as key "myName" and
// the field is omitted from the object if its value is empty,
// as defined above.
Field int `gorethink:"myName,omitempty"`
// Field appears as key "Field" (the default), but
// the field is skipped if empty.
// Note the leading comma.
Field int `gorethink:",omitempty"`
Example (Int)

Convert a Go integer to a ReQL object 

cur, err := Expr(1).Run(session)
if err != nil {
	fmt.Print(err)
	return
}

var res interface{}
err = cur.One(&res)
if err != nil {
	fmt.Print(err)
	return
}

jsonPrint(res)

Output:

1
Example (Map)

Convert a Go slice to a ReQL object 

cur, err := Expr(map[string]interface{}{
	"a": 1,
	"b": "b",
}).Run(session)
if err != nil {
	fmt.Print(err)
	return
}

var res interface{}
err = cur.One(&res)
if err != nil {
	fmt.Print(err)
	return
}

jsonPrint(res)

Output:

{
    "a": 1,
    "b": "b"
}
Example (Slice)

Convert a Go slice to a ReQL object 

cur, err := Expr([]int{1, 2, 3}).Run(session)
if err != nil {
	fmt.Print(err)
	return
}

var res []interface{}
err = cur.All(&res)
if err != nil {
	fmt.Print(err)
	return
}

jsonPrint(res)

Output:

[
    1,
    2,
    3
]
Example (Struct)

Convert a Go slice to a ReQL object 

type ExampleTypeNested struct {
	N int
}

type ExampleTypeEmbed struct {
	C string
}

type ExampleTypeA struct {
	ExampleTypeEmbed

	A      int
	B      string
	Nested ExampleTypeNested
}

cur, err := Expr(ExampleTypeA{
	A: 1,
	B: "b",
	ExampleTypeEmbed: ExampleTypeEmbed{
		C: "c",
	},
	Nested: ExampleTypeNested{
		N: 2,
	},
}).Run(session)
if err != nil {
	fmt.Print(err)
	return
}

var res interface{}
err = cur.One(&res)
if err != nil {
	fmt.Print(err)
	return
}

jsonPrint(res)

Output:

{
    "A": 1,
    "B": "b",
    "C": "c",
    "Nested": {
        "N": 2
    }
}
Example (StructTags)

Convert a Go struct (with gorethink tags) to a ReQL object. The tags allow the field names to be changed. 

type ExampleType struct {
	A int    `gorethink:"field_a"`
	B string `gorethink:"field_b"`
}

cur, err := Expr(ExampleType{
	A: 1,
	B: "b",
}).Run(session)
if err != nil {
	fmt.Print(err)
	return
}

var res interface{}
err = cur.One(&res)
if err != nil {
	fmt.Print(err)
	return
}

jsonPrint(res)

Output:

{
    "field_a": 1,
    "field_b": "b"
}

func Ge 

func Ge(args ...interface{}) Term

Ge returns true if the first value is greater than or equal to the second.

func GeoJSON 

func GeoJSON(args ...interface{}) Term

GeoJSON converts a GeoJSON object to a ReQL geometry object.

func Gt 

func Gt(args ...interface{}) Term

Gt returns true if the first value is greater than the second.

func HTTP 

func HTTP(url interface{}, optArgs ...HTTPOpts) Term

HTTP retrieves data from the specified URL over HTTP. The return type depends on the resultFormat option, which checks the Content-Type of the response by default.

func ISO8601 

func ISO8601(date interface{}, optArgs ...ISO8601Opts) Term

ISO8601 returns a time object based on an ISO8601 formatted date-time string

func JS 

func JS(jssrc interface{}) Term

JS creates a JavaScript expression which is evaluated by the database when running the query.

func JSON 

func JSON(args ...interface{}) Term

JSON parses a JSON string on the server.

func Le 

func Le(args ...interface{}) Term

Le returns true if the first value is less than or equal to the second.

func Line 

func Line(args ...interface{}) Term

Line constructs a geometry object of type Line. The line can be specified in one of two ways:

  • Two or more two-item arrays, specifying longitude and latitude numbers of the line's vertices;
  • Two or more Point objects specifying the line's vertices.

func Literal 

func Literal(args ...interface{}) Term

Literal replaces an object in a field instead of merging it with an existing object in a merge or update operation.

func Lt 

func Lt(args ...interface{}) Term

Lt returns true if the first value is less than the second.

func Map 

func Map(args ...interface{}) Term

Map transform each element of the sequence by applying the given mapping function. It takes two arguments, a sequence and a function of type `func (r.Term) interface{}`.

For example this query doubles each element in an array: 

r.Map([]int{1,3,6}, func (row r.Term) interface{} {
    return row.Mul(2)
})
Example (MultipleSequences)

Sum the elements of three sequences. 

var sequence1 = []int{100, 200, 300, 400}
var sequence2 = []int{10, 20, 30, 40}
var sequence3 = []int{1, 2, 3, 4}

cur, err := Map(sequence1, sequence2, sequence3, func(val1, val2, val3 Term) Term {
	return val1.Add(val2).Add(val3)
}).Run(session)
if err != nil {
	fmt.Print(err)
	return
}

var res []int
err = cur.All(&res)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Print(res)

Output:

[111 222 333 444]

func Mod 

func Mod(args ...interface{}) Term

Mod divides two numbers and returns the remainder.

func Mul 

func Mul(args ...interface{}) Term

Mul multiplies two numbers.

func Ne 

func Ne(args ...interface{}) Term

Ne returns true if two values are not equal.

func Not 

func Not(args ...interface{}) Term

Not performs a logical not on a value.

func Now 

func Now(args ...interface{}) Term

Now returns a time object representing the current time in UTC

func Object 

func Object(args ...interface{}) Term

Object creates an object from a list of key-value pairs, where the keys must be strings.

func Or 

func Or(args ...interface{}) Term

Or performs a logical or on two values.

func Point 

func Point(lon, lat interface{}) Term

Point constructs a geometry object of type Point. The point is specified by two floating point numbers, the longitude (−180 to 180) and latitude (−90 to 90) of the point on a perfect sphere.

func Polygon 

func Polygon(args ...interface{}) Term

Polygon constructs a geometry object of type Polygon. The Polygon can be specified in one of two ways:

  • Three or more two-item arrays, specifying longitude and latitude numbers of the polygon's vertices;
  • Three or more Point objects specifying the polygon's vertices.

func Range 

func Range(args ...interface{}) Term

Range generates a stream of sequential integers in a specified range. It accepts 0, 1, or 2 arguments, all of which should be numbers.

func Sub 

func Sub(args ...interface{}) Term

Sub subtracts two numbers.

func Table 

func Table(name interface{}, optArgs ...TableOpts) Term

Table selects all documents in a table. This command can be chained with other commands to do further processing on the data.

There are two optional arguments.

  • useOutdated: if true, this allows potentially out-of-date data to be returned, with potentially faster reads. It also allows you to perform reads from a secondary replica if a primary has failed. Default false.
  • identifierFormat: possible values are name and uuid, with a default of name. If set to uuid, then system tables will refer to servers, databases and tables by UUID rather than name. (This only has an effect when used with system tables.)

func Time 

func Time(args ...interface{}) Term

Time creates a time object for a specific time

func UUID 

func UUID(args ...interface{}) Term

UUID returns a UUID (universally unique identifier), a string that can be used as a unique ID.

func Wait 

func Wait(optArgs ...WaitOpts) Term

Wait for a table or all the tables in a database to be ready. A table may be temporarily unavailable after creation, rebalancing or reconfiguring. The wait command blocks until the given table (or database) is fully up to date.

func (Term) Add 

func (t Term) Add(args ...interface{}) Term

Add sums two numbers or concatenates two arrays.

func (Term) And 

func (t Term) And(args ...interface{}) Term

And performs a logical and on two values.

func (Term) Append 

func (t Term) Append(args ...interface{}) Term

Append appends a value to an array.

func (Term) AtIndex 

func (t Term) AtIndex(args ...interface{}) Term

AtIndex gets a single field from an object or the nth element from a sequence.

func (Term) Avg 

func (t Term) Avg(args ...interface{}) Term

Avg returns the average of all the elements of a sequence. If called with a field name, averages all the values of that field in the sequence, skipping elements of the sequence that lack that field. If called with a function, calls that function on every element of the sequence and averages the results, skipping elements of the sequence where that function returns null or a non-existence error.

func (Term) Between 

func (t Term) Between(lowerKey, upperKey interface{}, optArgs ...BetweenOpts) Term

Between gets all documents between two keys. Accepts three optional arguments: index, leftBound, and rightBound. If index is set to the name of a secondary index, between will return all documents where that index’s value is in the specified range (it uses the primary key by default). leftBound or rightBound may be set to open or closed to indicate whether or not to include that endpoint of the range (by default, leftBound is closed and rightBound is open).

You may also use the special constants r.minval and r.maxval for boundaries, which represent “less than any index key” and “more than any index key” respectively. For instance, if you use r.minval as the lower key, then between will return all documents whose primary keys (or indexes) are less than the specified upper key.

func (Term) ChangeAt 

func (t Term) ChangeAt(args ...interface{}) Term

ChangeAt changes a value in an array at a given index. Returns the modified array.

func (Term) Changes 

func (t Term) Changes(optArgs ...ChangesOpts) Term

Changes returns an infinite stream of objects representing changes to a query.

func (Term) CoerceTo 

func (t Term) CoerceTo(args ...interface{}) Term

CoerceTo converts a value of one type into another.

You can convert: a selection, sequence, or object into an ARRAY, an array of pairs into an OBJECT, and any DATUM into a STRING.

func (Term) ConcatMap 

func (t Term) ConcatMap(args ...interface{}) Term

ConcatMap concatenates one or more elements into a single sequence using a mapping function. ConcatMap works in a similar fashion to Map, applying the given function to each element in a sequence, but it will always return a single sequence.

func (Term) Config 

func (t Term) Config() Term

Config can be used to read and/or update the configurations for individual tables or databases.

func (Term) Contains 

func (t Term) Contains(args ...interface{}) Term

Contains returns whether or not a sequence contains all the specified values, or if functions are provided instead, returns whether or not a sequence contains values matching all the specified functions.

func (Term) Count 

func (t Term) Count(args ...interface{}) Term

Count the number of elements in the sequence. With a single argument, count the number of elements equal to it. If the argument is a function, it is equivalent to calling filter before count.

func (Term) Date 

func (t Term) Date(args ...interface{}) Term

Date returns a new time object only based on the day, month and year (ie. the same day at 00:00).

func (Term) Day 

func (t Term) Day(args ...interface{}) Term

Day return the day of a time object as a number between 1 and 31.

func (Term) DayOfWeek 

func (t Term) DayOfWeek(args ...interface{}) Term

DayOfWeek returns the day of week of a time object as a number between 1 and 7 (following ISO 8601 standard). For your convenience, the terms r.Monday(), r.Tuesday() etc. are defined and map to the appropriate integer.

func (Term) DayOfYear 

func (t Term) DayOfYear(args ...interface{}) Term

DayOfYear returns the day of the year of a time object as a number between 1 and 366 (following ISO 8601 standard).

func (Term) Default 

func (t Term) Default(args ...interface{}) Term

Default handles non-existence errors. Tries to evaluate and return its first argument. If an error related to the absence of a value is thrown in the process, or if its first argument returns null, returns its second argument. (Alternatively, the second argument may be a function which will be called with either the text of the non-existence error or null.)

Example

Suppose we want to retrieve the titles and authors of the table posts. In the case where the author field is missing or null, we want to retrieve the string "Anonymous". 

cur, err := DB("examples").Table("posts").Map(map[string]interface{}{
	"title":  Row.Field("title"),
	"author": Row.Field("author").Default("Anonymous"),
}).Run(session)
if err != nil {
	fmt.Print(err)
	return
}

var res map[string]interface{}
err = cur.One(&res)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Print(res)

Output:

func (Term) Delete 

func (t Term) Delete(optArgs ...DeleteOpts) Term

Delete one or more documents from a table.

Example

Delete a single document from the table posts. 

resp, err := DB("examples").Table("posts").Get(2).Delete().RunWrite(session)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Printf("%d row deleted", resp.Deleted)

Output:

1 row deleted
Example (Many)

Delete all comments where the field status is published 

resp, err := DB("examples").Table("posts").Filter(map[string]interface{}{
	"status": "published",
}).Delete().RunWrite(session)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Printf("%d rows deleted", resp.Deleted)

Output:

4 rows deleted

func (Term) DeleteAt 

func (t Term) DeleteAt(args ...interface{}) Term

DeleteAt removes an element from an array at a given index. Returns the modified array.

func (Term) Difference 

func (t Term) Difference(args ...interface{}) Term

Difference removes the elements of one array from another array.

func (Term) Distance 

func (t Term) Distance(point interface{}, optArgs ...DistanceOpts) Term

Distance calculates the Haversine distance between two points. At least one of the geometry objects specified must be a point.

func (Term) Distinct 

func (t Term) Distinct(optArgs ...DistinctOpts) Term

Distinct removes duplicate elements from the sequence.

func (Term) Div 

func (t Term) Div(args ...interface{}) Term

Div divides two numbers.

func (Term) Do 

func (t Term) Do(args ...interface{}) Term

Do evaluates the expr in the context of one or more value bindings. The type of the result is the type of the value returned from expr.

func (Term) Downcase 

func (t Term) Downcase(args ...interface{}) Term

Downcase lower-cases a string.

func (Term) During 

func (t Term) During(startTime, endTime interface{}, optArgs ...DuringOpts) Term

During returns true if a time is between two other times (by default, inclusive for the start, exclusive for the end).

func (Term) Eq 

func (t Term) Eq(args ...interface{}) Term

Eq returns true if two values are equal.

func (Term) EqJoin 

func (t Term) EqJoin(left, right interface{}, optArgs ...EqJoinOpts) Term

EqJoin is an efficient join that looks up elements in the right table by primary key.

Optional arguments: "index" (string - name of the index to use in right table instead of the primary key)

func (Term) Exec 

func (t Term) Exec(s *Session, optArgs ...ExecOpts) error

Exec runs the query but does not return the result. Exec will still wait for the response to be received unless the NoReply field is true. 

err := r.Db("database").Table("table").Insert(doc).Exec(sess, r.ExecOpts{
	NoReply: true,
})

func (Term) Field 

func (t Term) Field(args ...interface{}) Term

Field gets a single field from an object. If called on a sequence, gets that field from every object in the sequence, skipping objects that lack it.

Example

Get john's age 

cur, err := DB("examples").Table("users").Get("john").Field("age").Run(session)
if err != nil {
	fmt.Print(err)
	return
}

var res int
err = cur.One(&res)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Print(res)

Output:

19

func (Term) Fill 

func (t Term) Fill() Term

Fill converts a Line object into a Polygon object. If the last point does not specify the same coordinates as the first point, polygon will close the polygon by connecting them

func (Term) Filter 

func (t Term) Filter(f interface{}, optArgs ...FilterOpts) Term

Filter gets all the documents for which the given predicate is true.

Filter can be called on a sequence, selection, or a field containing an array of elements. The return type is the same as the type on which the function was called on. The body of every filter is wrapped in an implicit `.default(false)`, and the default value can be changed by passing the optional argument `default`. Setting this optional argument to `r.error()` will cause any non-existence errors to abort the filter.

Example

Get all users who are 30 years old. 

// Fetch the row from the database
res, err := DB("examples").Table("users").Filter(map[string]interface{}{
	"age": 30,
}).Run(session)
if err != nil {
	fmt.Print(err)
	return
}
defer res.Close()

// Scan query result into the person variable
var users []interface{}
err = res.All(&users)
if err != nil {
	fmt.Print("Error scanning database result: %s", err)
	return
}
fmt.Printf("%d users", len(users))

Output:

2 users
Example (Function)

Retrieve all users who have a gmail account (whose field email ends with @gmail.com). 

// Fetch the row from the database
res, err := DB("examples").Table("users").Filter(func(user Term) Term {
	return user.Field("email").Match("@gmail.com$")
}).Run(session)
if err != nil {
	fmt.Print(err)
	return
}
defer res.Close()

// Scan query result into the person variable
var users []interface{}
err = res.All(&users)
if err != nil {
	fmt.Print("Error scanning database result: %s", err)
	return
}
fmt.Printf("%d users", len(users))

Output:

1 users
Example (Row)

Get all users who are more than 25 years old. 

// Fetch the row from the database
res, err := DB("examples").Table("users").Filter(Row.Field("age").Gt(25)).Run(session)
if err != nil {
	fmt.Print(err)
	return
}
defer res.Close()

// Scan query result into the person variable
var users []interface{}
err = res.All(&users)
if err != nil {
	fmt.Print("Error scanning database result: %s", err)
	return
}
fmt.Printf("%d users", len(users))

Output:

3 users

func (Term) ForEach 

func (t Term) ForEach(args ...interface{}) Term

ForEach loops over a sequence, evaluating the given write query for each element.

It takes one argument of type `func (r.Term) interface{}`, for example clones a table: 

r.Table("table").ForEach(func (row r.Term) interface{} {
    return r.Table("new_table").Insert(row)
})

func (Term) Ge 

func (t Term) Ge(args ...interface{}) Term

Ge returns true if the first value is greater than or equal to the second.

func (Term) Get 

func (t Term) Get(args ...interface{}) Term

Get gets a document by primary key. If nothing was found, RethinkDB will return a nil value.

Example

Find a document by ID. 

// Fetch the row from the database
res, err := DB("examples").Table("heroes").Get(2).Run(session)
if err != nil {
	fmt.Print(err)
	return
}
defer res.Close()

if res.IsNil() {
	fmt.Print("Row not found")
	return
}

var hero map[string]interface{}
err = res.One(&hero)
if err != nil {
	fmt.Print("Error scanning database result: %s", err)
	return
}
fmt.Print(hero["name"])

Output:

Superman
Example (Merge)

Find a document and merge another document with it. 

// Fetch the row from the database
res, err := DB("examples").Table("heroes").Get(4).Merge(map[string]interface{}{
	"powers": []string{"speed"},
}).Run(session)
if err != nil {
	fmt.Print(err)
	return
}
defer res.Close()

if res.IsNil() {
	fmt.Print("Row not found")
	return
}

var hero map[string]interface{}
err = res.One(&hero)
if err != nil {
	fmt.Print("Error scanning database result: %s", err)
	return
}
fmt.Printf("%s: %v", hero["name"], hero["powers"])

Output:

The Flash: [speed]

func (Term) GetAll 

func (t Term) GetAll(keys ...interface{}) Term

GetAll gets all documents where the given value matches the value of the primary index.

func (Term) GetAllByIndex 

func (t Term) GetAllByIndex(index interface{}, keys ...interface{}) Term

GetAllByIndex gets all documents where the given value matches the value of the requested index.

func (Term) GetIntersecting 

func (t Term) GetIntersecting(args interface{}, optArgs ...GetIntersectingOpts) Term

GetIntersecting gets all documents where the given geometry object intersects the geometry object of the requested geospatial index.

func (Term) GetNearest 

func (t Term) GetNearest(point interface{}, optArgs ...GetNearestOpts) Term

GetNearest gets all documents where the specified geospatial index is within a certain distance of the specified point (default 100 kilometers).

func (Term) Group 

func (t Term) Group(fieldOrFunctions ...interface{}) Term

Group takes a stream and partitions it into multiple groups based on the fields or functions provided. Commands chained after group will be called on each of these grouped sub-streams, producing grouped data.

Example

Group games by player. 

cur, err := DB("examples").Table("games").Group("player").Run(session)
if err != nil {
	fmt.Print(err)
	return
}

var res []interface{}
err = cur.All(&res)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Print(res)

Output:

func (Term) GroupByIndex 

func (t Term) GroupByIndex(index interface{}, fieldOrFunctions ...interface{}) Term

GroupByIndex takes a stream and partitions it into multiple groups based on the fields or functions provided. Commands chained after group will be called on each of these grouped sub-streams, producing grouped data.

Example

Group games by the index type. 

cur, err := DB("examples").Table("games").GroupByIndex("type").Run(session)
if err != nil {
	fmt.Print(err)
	return
}

var res []interface{}
err = cur.All(&res)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Print(res)

Output:

func (Term) Gt 

func (t Term) Gt(args ...interface{}) Term

Gt returns true if the first value is greater than the second.

func (Term) HasFields 

func (t Term) HasFields(args ...interface{}) Term

HasFields tests if an object has all of the specified fields. An object has a field if it has the specified key and that key maps to a non-null value. For instance, 

the object `{'a':1,'b':2,'c':null}` has the fields `a` and `b`.

func (Term) Hours 

func (t Term) Hours(args ...interface{}) Term

Hours returns the hour in a time object as a number between 0 and 23.

func (Term) InTimezone 

func (t Term) InTimezone(args ...interface{}) Term

InTimezone returns a new time object with a different time zone. While the time stays the same, the results returned by methods such as hours() will change since they take the timezone into account. The timezone argument has to be of the ISO 8601 format.

func (Term) Includes 

func (t Term) Includes(args ...interface{}) Term

Includes tests whether a geometry object is completely contained within another. When applied to a sequence of geometry objects, includes acts as a filter, returning a sequence of objects from the sequence that include the argument.

func (Term) IndexCreate 

func (t Term) IndexCreate(name interface{}, optArgs ...IndexCreateOpts) Term

IndexCreate creates a new secondary index on a table. Secondary indexes improve the speed of many read queries at the slight cost of increased storage space and decreased write performance.

IndexCreate supports the creation of the following types of indexes, to create indexes using arbitrary expressions use IndexCreateFunc.

  • Simple indexes based on the value of a single field.
  • Compound indexes based on multiple fields.
  • Multi indexes based on arrays of values, created when the multi optional argument is true.
  • Geospatial indexes based on indexes of geometry objects, created when the geo optional argument is true.
Example

Create a simple index based on the field name. 

// Setup database
DB("examples").TableDrop("table").Run(session)
DB("examples").TableCreate("table").Run(session)

response, err := DB("examples").Table("table").IndexCreate("name").RunWrite(session)
if err != nil {
	log.Fatalf("Error creating index: %s", err)
}

fmt.Printf("%d index created", response.Created)

Output:

1 index created
Example (Compound)

Create a compound index based on the fields first_name and last_name. 

// Setup database
DB("examples").TableDrop("table").Run(session)
DB("examples").TableCreate("table").Run(session)

response, err := DB("examples").Table("table").IndexCreateFunc("full_name", func(row Term) interface{} {
	return []interface{}{row.Field("first_name"), row.Field("last_name")}
}).RunWrite(session)
if err != nil {
	log.Fatalf("Error creating index: %s", err)
}

fmt.Printf("%d index created", response.Created)

Output:

1 index created

func (Term) IndexCreateFunc 

func (t Term) IndexCreateFunc(name, indexFunction interface{}, optArgs ...IndexCreateOpts) Term

IndexCreateFunc creates a new secondary index on a table. Secondary indexes improve the speed of many read queries at the slight cost of increased storage space and decreased write performance.

The indexFunction can be an anonymous function or a binary representation obtained from the function field of indexStatus.

func (Term) IndexDrop 

func (t Term) IndexDrop(args ...interface{}) Term

IndexDrop deletes a previously created secondary index of a table.

func (Term) IndexList 

func (t Term) IndexList(args ...interface{}) Term

IndexList lists all the secondary indexes of a table.

func (Term) IndexRename 

func (t Term) IndexRename(oldName, newName interface{}, optArgs ...IndexRenameOpts) Term

IndexRename renames an existing secondary index on a table.

func (Term) IndexStatus 

func (t Term) IndexStatus(args ...interface{}) Term

IndexStatus gets the status of the specified indexes on this table, or the status of all indexes on this table if no indexes are specified.

func (Term) IndexWait 

func (t Term) IndexWait(args ...interface{}) Term

IndexWait waits for the specified indexes on this table to be ready, or for all indexes on this table to be ready if no indexes are specified.

func (Term) Info 

func (t Term) Info(args ...interface{}) Term

Info gets information about a RQL value.

func (Term) InnerJoin 

func (t Term) InnerJoin(args ...interface{}) Term

InnerJoin returns the inner product of two sequences (e.g. a table, a filter result) filtered by the predicate. The query compares each row of the left sequence with each row of the right sequence to find all pairs of rows which satisfy the predicate. When the predicate is satisfied, each matched pair of rows of both sequences are combined into a result row.

func (Term) Insert 

func (t Term) Insert(arg interface{}, optArgs ...InsertOpts) Term

Insert documents into a table. Accepts a single document or an array of documents.

Example (GeneratedKey)

Insert a document without a defined primary key into the table posts where the primary key is id. 

type Post struct {
	Title   string `gorethink:"title"`
	Content string `gorethink:"content"`
}

resp, err := DB("examples").Table("posts").Insert(map[string]interface{}{
	"title":   "Lorem ipsum",
	"content": "Dolor sit amet",
}).RunWrite(session)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Printf("%d row inserted, %d key generated", resp.Inserted, len(resp.GeneratedKeys))

Output:

1 row inserted, 1 key generated
Example (Map)

Insert a document into the table posts using a map. 

resp, err := DB("examples").Table("posts").Insert(map[string]interface{}{
	"id":      2,
	"title":   "Lorem ipsum",
	"content": "Dolor sit amet",
}).RunWrite(session)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Printf("%d row inserted", resp.Inserted)

Output:

1 row inserted
Example (Multiple)

Insert multiple documents into the table posts. 

resp, err := DB("examples").Table("posts").Insert([]interface{}{
	map[string]interface{}{
		"title":   "Lorem ipsum",
		"content": "Dolor sit amet",
	},
	map[string]interface{}{
		"title":   "Lorem ipsum",
		"content": "Dolor sit amet",
	},
}).RunWrite(session)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Printf("%d rows inserted", resp.Inserted)

Output:

2 rows inserted
Example (Struct)

Insert a document into the table posts using a struct. 

type Post struct {
	ID      int    `gorethink:"id"`
	Title   string `gorethink:"title"`
	Content string `gorethink:"content"`
}

resp, err := DB("examples").Table("posts").Insert(Post{
	ID:      1,
	Title:   "Lorem ipsum",
	Content: "Dolor sit amet",
}).RunWrite(session)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Printf("%d row inserted", resp.Inserted)

Output:

1 row inserted
Example (Upsert)

Insert a document into the table posts, replacing the document if it already exists. 

resp, err := DB("examples").Table("posts").Insert(map[string]interface{}{
	"id":    1,
	"title": "Lorem ipsum 2",
}, InsertOpts{
	Conflict: "replace",
}).RunWrite(session)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Printf("%d row replaced", resp.Replaced)

Output:

1 row replaced

func (Term) InsertAt 

func (t Term) InsertAt(args ...interface{}) Term

InsertAt inserts a value in to an array at a given index. Returns the modified array.

func (Term) Intersects 

func (t Term) Intersects(args ...interface{}) Term

Intersects tests whether two geometry objects intersect with one another. When applied to a sequence of geometry objects, intersects acts as a filter, returning a sequence of objects from the sequence that intersect with the argument.

func (Term) IsEmpty 

func (t Term) IsEmpty(args ...interface{}) Term

IsEmpty tests if a sequence is empty.

func (Term) Keys 

func (t Term) Keys(args ...interface{}) Term

Keys returns an array containing all of the object's keys.

func (Term) Le 

func (t Term) Le(args ...interface{}) Term

Le returns true if the first value is less than or equal to the second.

func (Term) Limit 

func (t Term) Limit(args ...interface{}) Term

Limit ends the sequence after the given number of elements.

func (Term) Lt 

func (t Term) Lt(args ...interface{}) Term

Lt returns true if the first value is less than the second.

func (Term) Map 

func (t Term) Map(args ...interface{}) Term

Map transforms each element of the sequence by applying the given mapping function. It takes one argument of type `func (r.Term) interface{}`.

For example this query doubles each element in an array: 

r.Expr([]int{1,3,6}).Map(func (row r.Term) interface{} {
    return row.Mul(2)
})
Example

Return the first five squares. 

cur, err := Expr([]int{1, 2, 3, 4, 5}).Map(func(val Term) Term {
	return val.Mul(val)
}).Run(session)
if err != nil {
	fmt.Print(err)
	return
}

var res []int
err = cur.All(&res)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Print(res)

Output:

[1 4 9 16 25]

func (Term) Match 

func (t Term) Match(args ...interface{}) Term

Match matches against a regular expression. If no match is found, returns null. If there is a match then an object with the following fields is returned: 

str: The matched string
start: The matched string’s start
end: The matched string’s end
groups: The capture groups defined with parentheses

Accepts RE2 syntax (https://code.google.com/p/re2/wiki/Syntax). You can enable case-insensitive matching by prefixing the regular expression with (?i). See the linked RE2 documentation for more flags.

The match command does not support backreferences.

func (Term) Max 

func (t Term) Max(args ...interface{}) Term

Max finds the maximum of a sequence. If called with a field name, finds the element of that sequence with the largest value in that field. If called with a function, calls that function on every element of the sequence and returns the element which produced the largest value, ignoring any elements where the function returns null or produces a non-existence error.

func (Term) MaxIndex 

func (t Term) MaxIndex(index interface{}, args ...interface{}) Term

MaxIndex finds the maximum of a sequence. If called with a field name, finds the element of that sequence with the largest value in that field. If called with a function, calls that function on every element of the sequence and returns the element which produced the largest value, ignoring any elements where the function returns null or produces a non-existence error.

func (Term) Merge 

func (t Term) Merge(args ...interface{}) Term

Merge merges two objects together to construct a new object with properties from both. Gives preference to attributes from other when there is a conflict.

func (Term) Min 

func (t Term) Min(args ...interface{}) Term

Min finds the minimum of a sequence. If called with a field name, finds the element of that sequence with the smallest value in that field. If called with a function, calls that function on every element of the sequence and returns the element which produced the smallest value, ignoring any elements where the function returns null or produces a non-existence error.

func (Term) MinIndex 

func (t Term) MinIndex(index interface{}, args ...interface{}) Term

MinIndex finds the minimum of a sequence. If called with a field name, finds the element of that sequence with the smallest value in that field. If called with a function, calls that function on every element of the sequence and returns the element which produced the smallest value, ignoring any elements where the function returns null or produces a non-existence error.

func (Term) Minutes 

func (t Term) Minutes(args ...interface{}) Term

Minutes returns the minute in a time object as a number between 0 and 59.

func (Term) Mod 

func (t Term) Mod(args ...interface{}) Term

Mod divides two numbers and returns the remainder.

func (Term) Month 

func (t Term) Month(args ...interface{}) Term

Month returns the month of a time object as a number between 1 and 12. For your convenience, the terms r.January(), r.February() etc. are defined and map to the appropriate integer.

func (Term) Mul 

func (t Term) Mul(args ...interface{}) Term

Mul multiplies two numbers.

func (Term) MultiGroup 

func (t Term) MultiGroup(fieldOrFunctions ...interface{}) Term

MultiGroup takes a stream and partitions it into multiple groups based on the fields or functions provided. Commands chained after group will be called on each of these grouped sub-streams, producing grouped data.

Unlike Group single documents can be assigned to multiple groups, similar to the behavior of multi-indexes. When the grouping value is an array, documents will be placed in each group that corresponds to the elements of the array. If the array is empty the row will be ignored.

Example

Suppose that the table games2 has the following data: 

  [
	     { id: 1, matches: {'a': [1, 2, 3], 'b': [4, 5, 6]} },
	     { id: 2, matches: {'b': [100], 'c': [7, 8, 9]} },
	     { id: 3, matches: {'a': [10, 20], 'c': [70, 80]} }
  ]

Using MultiGroup we can group data by match A, B or C. 

cur, err := DB("examples").Table("games2").MultiGroup(Row.Field("matches").Keys()).Run(session)
if err != nil {
	fmt.Print(err)
	return
}

var res []interface{}
err = cur.All(&res)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Print(res)

Output:

func (Term) MultiGroupByIndex 

func (t Term) MultiGroupByIndex(index interface{}, fieldOrFunctions ...interface{}) Term

MultiGroupByIndex takes a stream and partitions it into multiple groups based on the fields or functions provided. Commands chained after group will be called on each of these grouped sub-streams, producing grouped data.

Unlike Group single documents can be assigned to multiple groups, similar to the behavior of multi-indexes. When the grouping value is an array, documents will be placed in each group that corresponds to the elements of the array. If the array is empty the row will be ignored.

func (Term) Ne 

func (t Term) Ne(args ...interface{}) Term

Ne returns true if two values are not equal.

func (Term) Not 

func (t Term) Not(args ...interface{}) Term

Not performs a logical not on a value.

func (Term) Nth 

func (t Term) Nth(args ...interface{}) Term

Nth gets the nth element from a sequence.

func (Term) OffsetsOf 

func (t Term) OffsetsOf(args ...interface{}) Term

OffsetsOf gets the indexes of an element in a sequence. If the argument is a predicate, get the indexes of all elements matching it.

func (Term) Or 

func (t Term) Or(args ...interface{}) Term

Or performs a logical or on two values.

func (Term) OrderBy 

func (t Term) OrderBy(args ...interface{}) Term

OrderBy sorts the sequence by document values of the given key(s). To specify the ordering, wrap the attribute with either r.Asc or r.Desc (defaults to ascending).

Sorting without an index requires the server to hold the sequence in memory, and is limited to 100,000 documents (or the setting of the ArrayLimit option for run). Sorting with an index can be done on arbitrarily large tables, or after a between command using the same index.

Example (Compound)

You can efficiently order using multiple fields by using a compound index. For example order by date and title. 

cur, err := DB("examples").Table("posts").OrderBy(OrderByOpts{
	Index: Desc("dateAndTitle"),
}).Run(session)
if err != nil {
	fmt.Print(err)
	return
}

var res []interface{}
err = cur.All(&res)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Print(res)

Output:
Example (Index)

Order all the posts using the index date. 

cur, err := DB("examples").Table("posts").OrderBy(OrderByOpts{
	Index: "date",
}).Run(session)
if err != nil {
	fmt.Print(err)
	return
}

var res []interface{}
err = cur.All(&res)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Print(res)

Output:
Example (IndexDesc)

Order all the posts using the index date in descending order. 

cur, err := DB("examples").Table("posts").OrderBy(OrderByOpts{
	Index: Desc("date"),
}).Run(session)
if err != nil {
	fmt.Print(err)
	return
}

var res []interface{}
err = cur.All(&res)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Print(res)

Output:
Example (Multiple)

If you have a sequence with fewer documents than the arrayLimit, you can order it by multiple fields without an index. 

cur, err := DB("examples").Table("posts").OrderBy(
	"title",
	OrderByOpts{Index: Desc("date")},
).Run(session)
if err != nil {
	fmt.Print(err)
	return
}

var res []interface{}
err = cur.All(&res)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Print(res)

Output:
Example (MultipleWithIndex)

Notice that an index ordering always has highest precedence. The following query orders posts by date, and if multiple posts were published on the same date, they will be ordered by title. 

cur, err := DB("examples").Table("posts").OrderBy(
	"title",
	OrderByOpts{Index: Desc("date")},
).Run(session)
if err != nil {
	fmt.Print(err)
	return
}

var res []interface{}
err = cur.All(&res)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Print(res)

Output:

func (Term) OuterJoin 

func (t Term) OuterJoin(args ...interface{}) Term

OuterJoin computes a left outer join by retaining each row in the left table even if no match was found in the right table.

func (Term) Pluck 

func (t Term) Pluck(args ...interface{}) Term

Pluck plucks out one or more attributes from either an object or a sequence of objects (projection).

func (Term) PolygonSub 

func (t Term) PolygonSub(args ...interface{}) Term

PolygonSub "punches a hole" out of the parent polygon using the polygon passed to the function. 

polygon1.PolygonSub(polygon2) -> polygon

In the example above polygon2 must be completely contained within polygon1 and must have no holes itself (it must not be the output of polygon_sub itself).

func (Term) Prepend 

func (t Term) Prepend(args ...interface{}) Term

Prepend prepends a value to an array.

func (Term) Random 

func (t Term) Random(args ...interface{}) Term

Random generates a random number between the given bounds. If no arguments are given, the result will be a floating-point number in the range [0,1).

When passing a single argument, r.random(x), the result will be in the range [0,x), and when passing two arguments, r.random(x,y), the range is [x,y). If x and y are equal, an error will occur, unless generating a floating-point number, for which x will be returned.

Note: The last argument given will always be the 'open' side of the range, but when generating a floating-point number, the 'open' side may be less than the 'closed' side.

func (Term) Rebalance 

func (t Term) Rebalance() Term

Rebalance rebalances the shards of a table. When called on a database, all the tables in that database will be rebalanced.

func (Term) Reconfigure 

func (t Term) Reconfigure(opts ReconfigureOpts) Term

Reconfigure a table's sharding and replication.

func (Term) Reduce 

func (t Term) Reduce(args ...interface{}) Term

Reduce produces a single value from a sequence through repeated application of a reduction function

It takes one argument of type `func (r.Term, r.Term) interface{}`, for example this query sums all elements in an array: 

r.Expr([]int{1,3,6}).Reduce(func (left, right r.Term) interface{} {
    return left.Add(right)
})
Example

Return the number of documents in the table posts. 

cur, err := DB("examples").Table("posts").
	Map(func(doc Term) interface{} {
		return 1
	}).
	Reduce(func(left, right Term) interface{} {
		return left.Add(right)
	}).
	Run(session)
if err != nil {
	fmt.Print(err)
	return
}

var res int
err = cur.One(&res)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Print(res)

Output:

func (Term) Replace 

func (t Term) Replace(arg interface{}, optArgs ...ReplaceOpts) Term

Replace documents in a table. Accepts a JSON document or a ReQL expression, and replaces the original document with the new one. The new document must have the same primary key as the original document.

func (Term) Run 

func (t Term) Run(s *Session, optArgs ...RunOpts) (*Cursor, error)

Run runs a query using the given connection. 

	rows, err := query.Run(sess)
	if err != nil {
		// error
	}

 var doc MyDocumentType
	for rows.Next(&doc) {
     // Do something with document
	}

func (Term) RunWrite 

func (t Term) RunWrite(s *Session, optArgs ...RunOpts) (WriteResponse, error)

RunWrite runs a query using the given connection but unlike Run automatically scans the result into a variable of type WriteResponss. This function should be used if you are running a write query (such as Insert, Update, TableCreate, etc...).

If an error occurs when running the write query the first error is returned. 

res, err := r.Db("database").Table("table").Insert(doc).RunWrite(sess)

func (Term) Sample 

func (t Term) Sample(args ...interface{}) Term

Sample selects a given number of elements from a sequence with uniform random distribution. Selection is done without replacement.

func (Term) Seconds 

func (t Term) Seconds(args ...interface{}) Term

Seconds returns the seconds in a time object as a number between 0 and 59.999 (double precision).

func (Term) SetDifference 

func (t Term) SetDifference(args ...interface{}) Term

SetDifference removes the elements of one array from another and return them as a set (an array with distinct values).

func (Term) SetInsert 

func (t Term) SetInsert(args ...interface{}) Term

SetInsert adds a value to an array and return it as a set (an array with distinct values).

func (Term) SetIntersection 

func (t Term) SetIntersection(args ...interface{}) Term

SetIntersection calculates the intersection of two arrays returning values that occur in both of them as a set (an array with distinct values).

func (Term) SetUnion 

func (t Term) SetUnion(args ...interface{}) Term

SetUnion adds several values to an array and return it as a set (an array with distinct values).

func (Term) Skip 

func (t Term) Skip(args ...interface{}) Term

Skip skips a number of elements from the head of the sequence.

func (Term) Slice 

func (t Term) Slice(args ...interface{}) Term

Slice trims the sequence to within the bounds provided.

func (Term) SpliceAt 

func (t Term) SpliceAt(args ...interface{}) Term

SpliceAt inserts several values in to an array at a given index. Returns the modified array.

func (Term) Split 

func (t Term) Split(args ...interface{}) Term

Split splits a string into substrings. Splits on whitespace when called with no arguments. When called with a separator, splits on that separator. When called with a separator and a maximum number of splits, splits on that separator at most max_splits times. (Can be called with null as the separator if you want to split on whitespace while still specifying max_splits.)

Mimics the behavior of Python's string.split in edge cases, except for splitting on the empty string, which instead produces an array of single-character strings.

func (Term) Status 

func (t Term) Status() Term

Status return the status of a table

func (Term) String 

func (t Term) String() string

String returns a string representation of the query tree

func (Term) Sub 

func (t Term) Sub(args ...interface{}) Term

Sub subtracts two numbers.

func (Term) Sum 

func (t Term) Sum(args ...interface{}) Term

Sum returns the sum of all the elements of a sequence. If called with a field name, sums all the values of that field in the sequence, skipping elements of the sequence that lack that field. If called with a function, calls that function on every element of the sequence and sums the results, skipping elements of the sequence where that function returns null or a non-existence error.

func (Term) Sync 

func (t Term) Sync(args ...interface{}) Term

Sync ensures that writes on a given table are written to permanent storage. Queries that specify soft durability do not give such guarantees, so Sync can be used to ensure the state of these queries. A call to Sync does not return until all previous writes to the table are persisted.

func (Term) Table 

func (t Term) Table(name interface{}, optArgs ...TableOpts) Term

Table selects all documents in a table. This command can be chained with other commands to do further processing on the data.

There are two optional arguments.

  • useOutdated: if true, this allows potentially out-of-date data to be returned, with potentially faster reads. It also allows you to perform reads from a secondary replica if a primary has failed. Default false.
  • identifierFormat: possible values are name and uuid, with a default of name. If set to uuid, then system tables will refer to servers, databases and tables by UUID rather than name. (This only has an effect when used with system tables.)

func (Term) TableCreate 

func (t Term) TableCreate(name interface{}, optArgs ...TableCreateOpts) Term

TableCreate creates a table. A RethinkDB table is a collection of JSON documents.

Note: Only alphanumeric characters and underscores are valid for the table name.

Example

Create a table named "table" with the default settings. 

// Setup database
DB("examples").TableDrop("table").Run(session)

response, err := DB("examples").TableCreate("table").RunWrite(session)
if err != nil {
	log.Fatalf("Error creating table: %s", err)
}

fmt.Printf("%d table created", response.TablesCreated)

Output:

1 table created

func (Term) TableDrop 

func (t Term) TableDrop(args ...interface{}) Term

TableDrop deletes a table. The table and all its data will be deleted.

func (Term) TableList 

func (t Term) TableList(args ...interface{}) Term

TableList lists all table names in a database.

func (Term) TimeOfDay 

func (t Term) TimeOfDay(args ...interface{}) Term

TimeOfDay returns the number of seconds elapsed since the beginning of the day stored in the time object.

func (Term) Timezone 

func (t Term) Timezone(args ...interface{}) Term

Timezone returns the timezone of the time object

func (Term) ToEpochTime 

func (t Term) ToEpochTime(args ...interface{}) Term

ToEpochTime converts a time object to its epoch time.

func (Term) ToGeoJSON 

func (t Term) ToGeoJSON(args ...interface{}) Term

ToGeoJSON converts a ReQL geometry object to a GeoJSON object.

func (Term) ToISO8601 

func (t Term) ToISO8601(args ...interface{}) Term

ToISO8601 converts a time object to its iso 8601 format.

func (Term) ToJSON 

func (t Term) ToJSON() Term

ToJSON converts a ReQL value or object to a JSON string.

func (Term) TypeOf 

func (t Term) TypeOf(args ...interface{}) Term

TypeOf gets the type of a value.

func (Term) Ungroup 

func (t Term) Ungroup(args ...interface{}) Term

Ungroup takes a grouped stream or grouped data and turns it into an array of objects representing the groups. Any commands chained after Ungroup will operate on this array, rather than operating on each group individually. This is useful if you want to e.g. order the groups by the value of their reduction.

Example

Ungrouping grouped data. 

cur, err := DB("examples").Table("games").
	Group("player").
	Max("points").Field("points").
	Ungroup().
	Run(session)
if err != nil {
	fmt.Print(err)
	return
}

var res []interface{}
err = cur.All(&res)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Print(res)

Output:

func (Term) Union 

func (t Term) Union(args ...interface{}) Term

Union concatenates two sequences.

func (Term) Upcase 

func (t Term) Upcase(args ...interface{}) Term

Upcase upper-cases a string.

func (Term) Update 

func (t Term) Update(arg interface{}, optArgs ...UpdateOpts) Term

Update JSON documents in a table. Accepts a JSON document, a ReQL expression, or a combination of the two. You can pass options like returnChanges that will return the old and new values of the row you have modified.

Example

Update the status of the post with id of 1 to published. 

resp, err := DB("examples").Table("posts").Get(2).Update(map[string]interface{}{
	"status": "published",
}).RunWrite(session)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Printf("%d row replaced", resp.Replaced)

Output:

1 row replaced
Example (All)

Update the status of all posts to published. 

resp, err := DB("examples").Table("posts").Update(map[string]interface{}{
	"status": "published",
}).RunWrite(session)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Printf("%d row replaced", resp.Replaced)

Output:

4 row replaced
Example (Increment)

Increment the field view of the post with id of 1. If the field views does not exist, it will be set to 0. 

resp, err := DB("examples").Table("posts").Get(1).Update(map[string]interface{}{
	"views": Row.Field("views").Add(1).Default(0),
}).RunWrite(session)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Printf("%d row replaced", resp.Replaced)

Output:

1 row replaced
Example (Nested)

Update bob's cell phone number. 

resp, err := DB("examples").Table("users").Get("bob").Update(map[string]interface{}{
	"contact": map[string]interface{}{
		"phone": "408-555-4242",
	},
}).RunWrite(session)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Printf("%d row replaced", resp.Replaced)

Output:

1 row replaced
Example (SoftDurability)

Update the status of the post with id of 1 using soft durability. 

resp, err := DB("examples").Table("posts").Get(2).Update(map[string]interface{}{
	"status": "draft",
}, UpdateOpts{
	Durability: "soft",
}).RunWrite(session)
if err != nil {
	fmt.Print(err)
	return
}

fmt.Printf("%d row replaced", resp.Replaced)

Output:

1 row replaced

func (Term) Wait 

func (t Term) Wait(optArgs ...WaitOpts) Term

Wait for a table or all the tables in a database to be ready. A table may be temporarily unavailable after creation, rebalancing or reconfiguring. The wait command blocks until the given table (or database) is fully up to date.

func (Term) WithFields 

func (t Term) WithFields(args ...interface{}) Term

WithFields takes a sequence of objects and a list of fields. If any objects in the sequence don't have all of the specified fields, they're dropped from the sequence. The remaining objects have the specified fields plucked out. (This is identical to `HasFields` followed by `Pluck` on a sequence.)

func (Term) Without 

func (t Term) Without(args ...interface{}) Term

Without is the opposite of pluck; takes an object or a sequence of objects, and returns them with the specified paths removed.

func (Term) Year 

func (t Term) Year(args ...interface{}) Term

Year returns the year of a time object.

func (Term) Zip 

func (t Term) Zip(args ...interface{}) Term

Zip is used to 'zip' up the result of a join by merging the 'right' fields into 'left' fields of each member of the sequence.

type UpdateOpts 

type UpdateOpts struct {
	Durability    interface{} `gorethink:"durability,omitempty"`
	ReturnChanges interface{} `gorethink:"return_changes,omitempty"`
	NotAtomic     interface{} `gorethink:"non_atomic,omitempty"`
}

UpdateOpts contains the optional arguments for the Update term

type WaitOpts 

type WaitOpts struct {
	WaitFor interface{} `gorethink:"wait_for,omitempty"`
	Timeout interface{} `gorethink:"timeout,omitempty"`
}

WaitOpts contains the optional arguments for the Wait term.

type WriteResponse 

type WriteResponse struct {
	Errors        int              `gorethink:"errors"`
	Inserted      int              `gorethink:"inserted"`
	Updated       int              `gorethink:"updated"`
	Unchanged     int              `gorethink:"unchanged"`
	Replaced      int              `gorethink:"replaced"`
	Renamed       int              `gorethink:"renamed"`
	Skipped       int              `gorethink:"skipped"`
	Deleted       int              `gorethink:"deleted"`
	Created       int              `gorethink:"created"`
	DBsCreated    int              `gorethink:"dbs_created"`
	TablesCreated int              `gorethink:"tables_created"`
	Dropped       int              `gorethink:"dropped"`
	DBsDropped    int              `gorethink:"dbs_dropped"`
	TablesDropped int              `gorethink:"tables_dropped"`
	GeneratedKeys []string         `gorethink:"generated_keys"`
	FirstError    string           `gorethink:"first_error"` // populated if Errors > 0
	ConfigChanges []ChangeResponse `gorethink:"config_changes"`
	Changes       []ChangeResponse
}

WriteResponse is a helper type used when dealing with the response of a write query. It is also returned by the RunWrite function.

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