Documentation
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Index ¶
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.
Variables ¶
This section is empty.
Functions ¶
func ValidateSnapshotReadTS ¶
ValidateSnapshotReadTS strictly validates that readTS does not exceed the PD timestamp
Types ¶
type Context ¶
type Context interface {
SessionStatesHandler
// SetDiskFullOpt set the disk full opt when tikv disk full happened.
SetDiskFullOpt(level kvrpcpb.DiskFullOpt)
// RollbackTxn rolls back the current transaction.
RollbackTxn(ctx context.Context)
// CommitTxn commits the current transaction.
CommitTxn(ctx 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
// GetMPPClient gets a kv.MPPClient.
GetMPPClient() kv.MPPClient
// 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)
// Deprecated: the semantics of session.GetInfoSchema() is ambiguous
// If you want to get the infoschema of the current transaction in SQL layer, use sessiontxn.GetTxnManager(ctx).GetTxnInfoSchema()
// If you want to get the latest infoschema use `GetDomainInfoSchema`
GetInfoSchema() InfoschemaMetaVersion
// GetDomainInfoSchema returns the latest information schema in domain
// Different with `domain.InfoSchema()`, the information schema returned by this method
// includes the temporary table definitions stored in session
GetDomainInfoSchema() InfoschemaMetaVersion
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(context.Context) error
// RefreshVars refreshes modified global variable to current session.
// only used to daemon session like `statsHandle` to detect global variable change.
RefreshVars(context.Context) error
// GetStore returns the store of session.
GetStore() kv.Storage
// GetPlanCache returns the cache of the physical plan.
// generalPlanCache indicates to return the general plan cache or the prepared plan cache.
GetPlanCache(isGeneralPlanCache bool) PlanCache
// StoreQueryFeedback stores the query feedback.
StoreQueryFeedback(feedback interface{})
// UpdateColStatsUsage updates the column stats usage.
// TODO: maybe we can use a method called GetSessionStatsCollector to replace both StoreQueryFeedback and UpdateColStatsUsage but we need to deal with import circle if we do so.
UpdateColStatsUsage(predicateColumns []model.TableItemID)
// HasDirtyContent checks whether there's dirty update on the given table.
HasDirtyContent(tid int64) bool
// StmtCommit flush all changes by the statement to the underlying transaction.
StmtCommit()
// StmtRollback provides statement level rollback.
StmtRollback()
// StmtGetMutation gets the binlog mutation for current statement.
StmtGetMutation(int64) *binlog.TableMutation
// IsDDLOwner checks whether this session is DDL owner.
IsDDLOwner() bool
// AddTableLock adds table lock to the session lock map.
AddTableLock([]model.TableLockTpInfo)
// ReleaseTableLocks releases table locks in the session lock map.
ReleaseTableLocks(locks []model.TableLockTpInfo)
// ReleaseTableLockByTableIDs releases table locks in the session lock map by table IDs.
ReleaseTableLockByTableIDs(tableIDs []int64)
// CheckTableLocked checks the table lock.
CheckTableLocked(tblID int64) (bool, model.TableLockType)
// GetAllTableLocks gets all table locks table id and db id hold by the session.
GetAllTableLocks() []model.TableLockTpInfo
// ReleaseAllTableLocks releases all table locks hold by the session.
ReleaseAllTableLocks()
// HasLockedTables uses to check whether this session locked any tables.
HasLockedTables() bool
// PrepareTSFuture uses to prepare timestamp by future.
PrepareTSFuture(ctx context.Context, future oracle.Future, scope string) error
// GetPreparedTxnFuture returns the TxnFuture if it is valid or pending.
// It returns nil otherwise.
GetPreparedTxnFuture() TxnFuture
// StoreIndexUsage stores the index usage information.
StoreIndexUsage(tblID int64, idxID int64, rowsSelected int64)
// GetTxnWriteThroughputSLI returns the TxnWriteThroughputSLI.
GetTxnWriteThroughputSLI() *sli.TxnWriteThroughputSLI
// GetBuiltinFunctionUsage returns the BuiltinFunctionUsage of current Context, which is not thread safe.
// Use primitive map type to prevent circular import. Should convert it to telemetry.BuiltinFunctionUsage before using.
GetBuiltinFunctionUsage() map[string]uint32
// BuiltinFunctionUsageInc increase the counting of each builtin function usage
// Notice that this is a thread safe function
BuiltinFunctionUsageInc(scalarFuncSigName string)
// GetStmtStats returns stmtstats.StatementStats owned by implementation.
GetStmtStats() *stmtstats.StatementStats
// ShowProcess returns ProcessInfo running in current Context
ShowProcess() *util.ProcessInfo
// GetAdvisoryLock acquires an advisory lock (aka GET_LOCK()).
GetAdvisoryLock(string, int64) error
// ReleaseAdvisoryLock releases an advisory lock (aka RELEASE_LOCK()).
ReleaseAdvisoryLock(string) bool
// ReleaseAllAdvisoryLocks releases all advisory locks that this session holds.
ReleaseAllAdvisoryLocks() int
// GetExtensions returns the `*extension.SessionExtensions` object
GetExtensions() *extension.SessionExtensions
// InSandBoxMode indicates that this Session is in sandbox mode
// Ref about sandbox mode: https://dev.mysql.com/doc/refman/8.0/en/expired-password-handling.html
InSandBoxMode() bool
// EnableSandBoxMode enable the sandbox mode of this Session
EnableSandBoxMode()
// DisableSandBoxMode enable the sandbox mode of this Session
DisableSandBoxMode()
}
Context is an interface for transaction and executive args environment.
type InfoschemaMetaVersion ¶
type InfoschemaMetaVersion interface {
SchemaMetaVersion() int64
}
InfoschemaMetaVersion is a workaround. Due to circular dependency, can not return the complete interface. But SchemaMetaVersion is widely used for logging. So we give a convenience for that. FIXME: remove this interface
type PlanCache ¶
type PlanCache interface {
Get(key kvcache.Key, paramTypes []*types.FieldType) (value kvcache.Value, ok bool)
Put(key kvcache.Key, value kvcache.Value, paramTypes []*types.FieldType)
Delete(key kvcache.Key)
DeleteAll()
Size() int
SetCapacity(capacity uint) error
Close()
}
PlanCache is an interface for prepare and general plan cache
type SessionStatesHandler ¶
type SessionStatesHandler interface {
// EncodeSessionStates encodes session states into a JSON.
EncodeSessionStates(context.Context, Context, *sessionstates.SessionStates) error
// DecodeSessionStates decodes a map into session states.
DecodeSessionStates(context.Context, Context, *sessionstates.SessionStates) error
}
SessionStatesHandler is an interface for encoding and decoding session states.
type SysProcTracker ¶
type SysProcTracker interface {
Track(id uint64, proc Context) error
UnTrack(id uint64)
GetSysProcessList() map[uint64]*util.ProcessInfo
KillSysProcess(id uint64)
}
SysProcTracker is used to track background sys processes
type TxnFuture ¶
type TxnFuture interface {
// Wait converts pending txn to valid
Wait(ctx context.Context, sctx Context) (kv.Transaction, error)
}
TxnFuture is an interface where implementations have a kv.Transaction field and after calling Wait of the TxnFuture, the kv.Transaction will become valid.