sql

Documentation

Index

• Variables
• type Database
  • func InMemory(opts ...Opt) *Database
  • func Open(uri string, opts ...Opt) (*Database, error)
  • func (db *Database) Close() error
  • func (db *Database) Exec(query string, encoder Encoder, decoder Decoder) (int, error)
  • func (db *Database) Tx(ctx context.Context) (*Tx, error)
  • func (db *Database) TxImmediate(ctx context.Context) (*Tx, error)
  • func (db *Database) WithTx(ctx context.Context, exec func(*Tx) error) error
  • func (db *Database) WithTxImmediate(ctx context.Context, exec func(*Tx) error) error
• type Decoder
• type Encoder
• type Executor
• type Migrations
• type Opt
  • func WithConnections(n int) Opt
  • func WithLatencyMetering(enable bool) Opt
  • func WithMigrations(migrations Migrations) Opt
• type Statement
• type Tx
  • func (tx *Tx) Commit() error
  • func (tx *Tx) Exec(query string, encoder Encoder, decoder Decoder) (int, error)
  • func (tx *Tx) Release() error

Variables

var (
	// ErrNoConnection is returned if pooled connection is not available.
	ErrNoConnection = errors.New("database: no free connection")
	// ErrNotFound is returned if requested record is not found.
	ErrNotFound = errors.New("database: not found")
	// ErrObjectExists is returned if database constraints didn't allow to insert an object.
	ErrObjectExists = errors.New("database: object exists")
)

Types

type Database

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

Database is an instance of sqlite database.

func InMemory

func InMemory(opts ...Opt) *Database

InMemory database for testing.

func Open

func Open(uri string, opts ...Opt) (*Database, error)

Open database with options.

Database is opened in WAL mode and pragma synchronous=normal. https://sqlite.org/wal.html https://www.sqlite.org/pragma.html#pragma_synchronous

func (*Database) Close

func (db *Database) Close() error

Close closes all pooled connections.

func (*Database) Exec

func (db *Database) Exec(query string, encoder Encoder, decoder Decoder) (int, error)

Exec statement using one of the connection from the pool.

If you care about atomicity of the operation (for example writing rewards to multiple accounts) Tx should be used. Otherwise sqlite will not guarantee that all side-effects of operations are applied to the database if machine crashes.

Note that Exec will block until database is closed or statement has finished. If application needs to control statement execution lifetime use one of the transaction.

func (*Database) Tx

func (db *Database) Tx(ctx context.Context) (*Tx, error)

Tx creates deferred sqlite transaction.

Deferred transactions are not started until the first statement. Transaction may be started in read mode and automatically upgraded to write mode after one of the write statements.

https://www.sqlite.org/lang_transaction.html

func (*Database) TxImmediate

func (db *Database) TxImmediate(ctx context.Context) (*Tx, error)

TxImmediate creates immediate transaction.

IMMEDIATE cause the database connection to start a new write immediately, without waiting for a write statement. The BEGIN IMMEDIATE might fail with SQLITE_BUSY if another write transaction is already active on another database connection.

func (*Database) WithTx

func (db *Database) WithTx(ctx context.Context, exec func(*Tx) error) error

WithTx will pass initialized deferred transaction to exec callback. Will commit only if error is nil.

func (*Database) WithTxImmediate

func (db *Database) WithTxImmediate(ctx context.Context, exec func(*Tx) error) error

WithTxImmediate will pass initialized immediate transaction to exec callback. Will commit only if error is nil.

type Decoder

type Decoder func(*Statement) bool

Decoder for sqlite rows.

type Encoder

type Encoder func(*Statement)

Encoder for parameters. Both positional parameters: select block from blocks where id = ?1;

and named parameters are supported: select blocks from blocks where id = @id;

For complete information see https://www.sqlite.org/c3ref/bind_blob.html.

type Executor

type Executor interface {
	Exec(string, Encoder, Decoder) (int, error)
}

Executor is an interface for executing raw statement.

type Migrations

type Migrations func(Executor) error

Migrations is interface for migrations provider.

type Opt

type Opt func(c *conf)

Opt for configuring database.

func WithConnections

func WithConnections(n int) Opt

WithConnections overwrites number of pooled connections.

func WithLatencyMetering

func WithLatencyMetering(enable bool) Opt

WithLatencyMetering enables metric that track latency for every database query. Note that it will be a significant amount of data, and should not be enabled on multiple nodes by default.

func WithMigrations

func WithMigrations(migrations Migrations) Opt

WithMigrations overwrites embedded migrations.

type Statement

type Statement = sqlite.Stmt

Statement is an sqlite statement.

type Tx

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

Tx is wrapper for database transaction.

func (*Tx) Commit

func (tx *Tx) Commit() error

Commit transaction.

func (*Tx) Exec

func (tx *Tx) Exec(query string, encoder Encoder, decoder Decoder) (int, error)

Exec query.

func (*Tx) Release

func (tx *Tx) Release() error

Release transaction. Every transaction that was created must be released.