tidb

README

What is TiDB?

TiDB is a distributed SQL database. Inspired by the design of Google F1, TiDB supports the best features of both traditional RDBMS and NoSQL.

• Horizontal scalability
  Grow TiDB as your business grows. You can increase the capacity simply by adding more machines.

• Asynchronous schema changes
  Evolve TiDB schemas as your requirement evolves. You can add new columns and indices without stopping or affecting the on-going operations.

• Consistent distributed transactions
  Think TiDB as a single-machine RDBMS. You can start a transaction that acrosses multiple machines without worrying about consistency. TiDB makes your application code simple and robust.

• Compatible with MySQL protocol
  Use TiDB as MySQL. You can replace MySQL with TiDB to power your application without changing a single line of code in most cases.

• Written in Go
  Enjoy TiDB as much as we love Go. We believe Go code is both easy and enjoyable to work with. Go makes us improve TiDB fast and makes it easy to dive into the codebase.

• Multiple storage engine support
  Power TiDB with your most favorite engines. TiDB supports most of the popular storage engines in single-machine mode. You can choose from goleveldb, LevelDB, RocksDB, LMDB, BoltDB and even more to come.

Status

TiDB is at its early age and under heavy development, some of the features mentioned above have not been fully implemented.

Please do not use it in production.

Roadmap

Read the Roadmap.

Quick start

• Pre-requirement

go get -d github.com/pingcap/tidb
cd $GOPATH/src/github.com/pingcap/tidb
make

• Run command line interpreter

Interpreter is an interactive command line TiDB client. You can just enter some SQL statements and get the result.

make interpreter
cd interpreter && ./interpreter

Press Ctrl+C to quit.

• Run as go library
  See USAGE.md for detailed instructions to use TiDB as library in Go code.

• Run as MySQL protocol server with single-machine KV storage engine
  Comming soon.

• Run as MySQL protocol server with distributed transactional KV storage engine
  Comming soon.

Architecture

Contributing

Contributions are welcomed and greatly appreciated. See CONTRIBUTING.md for details on submitting patches and the contribution workflow.

Follow us

Twitter: @PingCAP

License

TiDB is under the Apache 2.0 license. See the LICENSE file for details.

Acknowledgments

• Thanks cznic for providing some great open source tools.
• Thanks GolevelDB, LMDB, BoltDB and RocksDB for their powerful storage engines.

Documentation

Index

• Constants
• Variables
• func Compile(src string) ([]stmt.Statement, error)
• func CompilePrepare(src string) (stmt.Statement, []*expressions.ParamMarker, error)
• func IsQuery(sql string) bool
• func NewStore(uri string) (kv.Storage, error)
• func RegisterDriver()
• func RegisterLocalStore(name string, driver engine.Driver) error
• func RegisterStore(name string, driver kv.Driver) error
• type Session
  • func CreateSession(store kv.Storage) (Session, error)

Constants

const (
	EngineGoLevelDBMemory     = "memory://"
	EngineGoLevelDBPersistent = "goleveldb://"
	EngineHBase               = "zk://"
	EngineBoltDB              = "boltdb://"
)

Engine prefix name

const (
	// DriverName is name of TiDB driver.
	DriverName = "tidb"
)

Variables

var (

	// Debug is the switch for pprof. If Debug is true, tidb will start with pprof on.
	Debug = true
	// PprofAddr is the pprof url.
	PprofAddr = "localhost:8888"
)

Functions

func Compile

func Compile(src string) ([]stmt.Statement, error)

Compile is safe for concurrent use by multiple goroutines.

func CompilePrepare

func CompilePrepare(src string) (stmt.Statement, []*expressions.ParamMarker, error)

CompilePrepare compiles prepared statement, allows placeholder as expr. The return values are compiled statement, parameter list and error.

func IsQuery

func IsQuery(sql string) bool

IsQuery checks if a sql statement is a query statement.

func NewStore

func NewStore(uri string) (kv.Storage, error)

NewStore creates a kv Storage with specific uri. The uri format must be engine://schema, like goleveldb://testpath Engine is the storage name registered with RegisterStore. Schema is the storage specific format.

func RegisterDriver

func RegisterDriver()

RegisterDriver registers TiDB driver. The name argument can be optionally prefixed by "engine://". In that case the prefix is recognized as a storage engine name.

The name argument can be optionally prefixed by "memory://". In that case the prefix is stripped before interpreting it as a name of a memory-only, volatile DB.

[0]: http://golang.org/pkg/database/sql/driver/

func RegisterLocalStore

func RegisterLocalStore(name string, driver engine.Driver) error

RegisterLocalStore registers a local kv storage with unique name and its associated engine Driver.

func RegisterStore

func RegisterStore(name string, driver kv.Driver) error

RegisterStore registers a kv storage with unique name and its associated Driver.

Types

type Session

type Session interface {
	Status() uint16                               // Flag of current status, such as autocommit
	LastInsertID() uint64                         // Last inserted auto_increment id
	AffectedRows() uint64                         // Affected rows by lastest executed stmt
	Execute(sql string) ([]rset.Recordset, error) // Execute a sql statement
	SetUsername(name string)                      // Current user name
	String() string                               // For debug
	FinishTxn(rollback bool) error
	// For execute prepare statement in binary protocol
	PrepareStmt(sql string) (stmtID uint32, paramCount int, fields []*field.ResultField, err error)
	// Execute a prepared statement
	ExecutePreparedStmt(stmtID uint32, param ...interface{}) (rset.Recordset, error)
	DropPreparedStmt(stmtID uint32) error
	SetClientCapability(uint32) // Set client capability flags
	Close() error
}

Session context

func CreateSession

func CreateSession(store kv.Storage) (Session, error)

CreateSession creates a new session environment.