sessionctx

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(context.Context) error

	// Txn returns the current transaction which is created before executing a statement.
	// The returned kv.Transaction is not nil, but it maybe pending or invalid.
	// If the active parameter is true, call this function will wait for the pending txn
	// to become valid.
	Txn(active bool) (kv.Transaction, error)

	// 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

	// 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
}