context

Documentation

Index

• Constants
• type Context

Constants

const (
	// QueryString is the key for original query string.
	QueryString basicCtxType = 1
	// Initing is the key for indicating if the server is running bootstrap or upgrade job.
	Initing basicCtxType = 2
	// LastExecuteDDL is the key for whether the session execute a ddl command last time.
	LastExecuteDDL basicCtxType = 3
)

Context keys.

Types

type Context

type Context interface {
	// NewTxn creates a new transaction for further execution.
	// If old transaction is valid, it is committed first.
	// It's used in BEGIN statement and DDL statements to commit old transaction.
	NewTxn() error

	// Txn returns the current transaction which is created before executing a statement.
	Txn() kv.Transaction

	// GetClient gets a kv.Client.
	GetClient() kv.Client

	// SetValue saves a value associated with this context for key.
	SetValue(key fmt.Stringer, value interface{})

	// Value returns the value associated with this context for key.
	Value(key fmt.Stringer) interface{}

	// ClearValue clears the value associated with this context for key.
	ClearValue(key fmt.Stringer)

	GetSessionVars() *variable.SessionVars

	GetSessionManager() util.SessionManager

	// RefreshTxnCtx commits old transaction without retry,
	// and creates a new transaction.
	// now just for load data and batch insert.
	RefreshTxnCtx(goctx.Context) error

	// ActivePendingTxn receives the pending transaction from the transaction channel.
	// It should be called right before we builds an executor.
	ActivePendingTxn() error

	// InitTxnWithStartTS initializes a transaction with startTS.
	// It should be called right before we builds an executor.
	InitTxnWithStartTS(startTS uint64) error

	// GetStore returns the store of session.
	GetStore() kv.Storage

	// PreparedPlanCache returns the cache of the physical plan
	PreparedPlanCache() *kvcache.SimpleLRUCache

	// StoreQueryFeedback stores the query feedback.
	StoreQueryFeedback(feedback interface{})
}

Context is an interface for transaction and executive args environment.