263 lines
9.5 KiB
Go
263 lines
9.5 KiB
Go
// Copyright 2024 PingCAP, Inc.
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
package exprctx
|
|
|
|
import (
|
|
"sync/atomic"
|
|
"time"
|
|
|
|
"github.com/pingcap/tidb/pkg/errctx"
|
|
"github.com/pingcap/tidb/pkg/parser/mysql"
|
|
"github.com/pingcap/tidb/pkg/sessionctx/variable"
|
|
"github.com/pingcap/tidb/pkg/types"
|
|
contextutil "github.com/pingcap/tidb/pkg/util/context"
|
|
"github.com/pingcap/tidb/pkg/util/intest"
|
|
"github.com/pingcap/tidb/pkg/util/mathutil"
|
|
)
|
|
|
|
// PlanColumnIDAllocator allocates column id for plan.
|
|
type PlanColumnIDAllocator interface {
|
|
// AllocPlanColumnID allocates column id for plan.
|
|
AllocPlanColumnID() int64
|
|
// GetLastPlanColumnID returns the last column id.
|
|
GetLastPlanColumnID() int64
|
|
}
|
|
|
|
var _ PlanColumnIDAllocator = &SimplePlanColumnIDAllocator{}
|
|
|
|
// SimplePlanColumnIDAllocator implements PlanColumnIDAllocator
|
|
type SimplePlanColumnIDAllocator struct {
|
|
id atomic.Int64
|
|
}
|
|
|
|
// NewSimplePlanColumnIDAllocator creates a new SimplePlanColumnIDAllocator.
|
|
func NewSimplePlanColumnIDAllocator(offset int64) *SimplePlanColumnIDAllocator {
|
|
alloc := &SimplePlanColumnIDAllocator{}
|
|
alloc.id.Store(offset)
|
|
return alloc
|
|
}
|
|
|
|
// AllocPlanColumnID allocates column id for plan.
|
|
func (a *SimplePlanColumnIDAllocator) AllocPlanColumnID() int64 {
|
|
return a.id.Add(1)
|
|
}
|
|
|
|
// GetLastPlanColumnID returns the last column id.
|
|
func (a *SimplePlanColumnIDAllocator) GetLastPlanColumnID() int64 {
|
|
return a.id.Load()
|
|
}
|
|
|
|
// EvalContext is used to evaluate an expression
|
|
type EvalContext interface {
|
|
contextutil.WarnHandler
|
|
ParamValues
|
|
// CtxID indicates the id of the context.
|
|
CtxID() uint64
|
|
// SQLMode returns the sql mode
|
|
SQLMode() mysql.SQLMode
|
|
// TypeCtx returns the types.Context
|
|
TypeCtx() types.Context
|
|
// ErrCtx returns the errctx.Context
|
|
ErrCtx() errctx.Context
|
|
// Location returns the timezone info
|
|
Location() *time.Location
|
|
// CurrentDB return the current database name
|
|
CurrentDB() string
|
|
// CurrentTime returns the current time.
|
|
// Multiple calls for CurrentTime() should return the same value for the same `CtxID`.
|
|
CurrentTime() (time.Time, error)
|
|
// GetMaxAllowedPacket returns the value of the 'max_allowed_packet' system variable.
|
|
GetMaxAllowedPacket() uint64
|
|
// GetTiDBRedactLog returns the value of the 'tidb_redact_log' system variable.
|
|
GetTiDBRedactLog() string
|
|
// GetDefaultWeekFormatMode returns the value of the 'default_week_format' system variable.
|
|
GetDefaultWeekFormatMode() string
|
|
// GetDivPrecisionIncrement returns the specified value of DivPrecisionIncrement.
|
|
GetDivPrecisionIncrement() int
|
|
// GetUserVarsReader returns the `UserVarsReader` to read user vars.
|
|
GetUserVarsReader() variable.UserVarsReader
|
|
// GetOptionalPropSet returns the optional properties provided by this context.
|
|
GetOptionalPropSet() OptionalEvalPropKeySet
|
|
// GetOptionalPropProvider gets the optional property provider by key
|
|
GetOptionalPropProvider(OptionalEvalPropKey) (OptionalEvalPropProvider, bool)
|
|
}
|
|
|
|
// BuildContext is used to build an expression
|
|
type BuildContext interface {
|
|
// GetEvalCtx returns the EvalContext.
|
|
GetEvalCtx() EvalContext
|
|
// GetCharsetInfo gets charset and collation for current context.
|
|
GetCharsetInfo() (string, string)
|
|
// GetDefaultCollationForUTF8MB4 returns the default collation of UTF8MB4.
|
|
GetDefaultCollationForUTF8MB4() string
|
|
// GetBlockEncryptionMode returns the variable `block_encryption_mode`.
|
|
GetBlockEncryptionMode() string
|
|
// GetSysdateIsNow returns a bool to determine whether Sysdate is an alias of Now function.
|
|
// It is the value of variable `tidb_sysdate_is_now`.
|
|
GetSysdateIsNow() bool
|
|
// GetNoopFuncsMode returns the noop function mode: OFF/ON/WARN values as 0/1/2.
|
|
GetNoopFuncsMode() int
|
|
// Rng is used to generate random values.
|
|
Rng() *mathutil.MysqlRng
|
|
// IsUseCache indicates whether to cache the build expression in plan cache.
|
|
IsUseCache() bool
|
|
// SetSkipPlanCache sets to skip the plan cache and records the reason.
|
|
SetSkipPlanCache(reason string)
|
|
// AllocPlanColumnID allocates column id for plan.
|
|
AllocPlanColumnID() int64
|
|
// IsInNullRejectCheck returns the flag to indicate whether the expression is in null reject check.
|
|
// It should always return `false` in most implementations because we do not want to do null reject check
|
|
// in most cases except for the method `isNullRejected` in planner.
|
|
// See the comments for `isNullRejected` in planner for more details.
|
|
IsInNullRejectCheck() bool
|
|
// IsConstantPropagateCheck returns the flag to indicate whether the expression is in constant propagate check.
|
|
// It should be true only when we are doing constant propagation in rule_predicate_push_down.
|
|
IsConstantPropagateCheck() bool
|
|
// ConnectionID indicates the connection ID of the current session.
|
|
// If the context is not in a session, it should return 0.
|
|
ConnectionID() uint64
|
|
// IsReadonlyUserVar checks whether the user variable is readonly.
|
|
IsReadonlyUserVar(name string) bool
|
|
}
|
|
|
|
// ExprContext contains full context for expression building and evaluating.
|
|
// It also provides some additional information for to build aggregate functions.
|
|
type ExprContext interface {
|
|
BuildContext
|
|
// GetWindowingUseHighPrecision determines whether to compute window operations without loss of precision.
|
|
// see https://dev.mysql.com/doc/refman/8.0/en/window-function-optimization.html for more details.
|
|
GetWindowingUseHighPrecision() bool
|
|
// GetGroupConcatMaxLen returns the value of the 'group_concat_max_len' system variable.
|
|
GetGroupConcatMaxLen() uint64
|
|
}
|
|
|
|
// NullRejectCheckExprContext is a wrapper to return true for `IsInNullRejectCheck`.
|
|
type NullRejectCheckExprContext struct {
|
|
ExprContext
|
|
}
|
|
|
|
// WithNullRejectCheck returns a new `NullRejectCheckExprContext` with the given `ExprContext`.
|
|
func WithNullRejectCheck(ctx ExprContext) *NullRejectCheckExprContext {
|
|
return &NullRejectCheckExprContext{ExprContext: ctx}
|
|
}
|
|
|
|
// IsInNullRejectCheck always returns true for `NullRejectCheckExprContext`
|
|
func (ctx *NullRejectCheckExprContext) IsInNullRejectCheck() bool {
|
|
return true
|
|
}
|
|
|
|
// ConstantPropagateCheckContext is a wrapper to return true for `IsConstantPropagateCheck`.
|
|
type ConstantPropagateCheckContext struct {
|
|
ExprContext
|
|
}
|
|
|
|
// WithConstantPropagateCheck returns a new `ConstantPropagateCheckContext` with the given `ExprContext`.
|
|
func WithConstantPropagateCheck(ctx ExprContext) *ConstantPropagateCheckContext {
|
|
return &ConstantPropagateCheckContext{ExprContext: ctx}
|
|
}
|
|
|
|
// IsConstantPropagateCheck always returns true for `ConstantPropagateCheckContext`
|
|
func (ctx *ConstantPropagateCheckContext) IsConstantPropagateCheck() bool {
|
|
return true
|
|
}
|
|
|
|
type innerOverrideEvalContext struct {
|
|
EvalContext
|
|
typeCtx types.Context
|
|
errCtx errctx.Context
|
|
}
|
|
|
|
// TypeCtx implements EvalContext.TypeCtx
|
|
func (ctx *innerOverrideEvalContext) TypeCtx() types.Context {
|
|
return ctx.typeCtx
|
|
}
|
|
|
|
// ErrCtx implements EvalContext.GetEvalCtx
|
|
func (ctx *innerOverrideEvalContext) ErrCtx() errctx.Context {
|
|
return ctx.errCtx
|
|
}
|
|
|
|
type innerOverrideBuildContext struct {
|
|
BuildContext
|
|
evalCtx EvalContext
|
|
}
|
|
|
|
// GetEvalCtx implements BuildContext.GetEvalCtx
|
|
func (ctx *innerOverrideBuildContext) GetEvalCtx() EvalContext {
|
|
return ctx.evalCtx
|
|
}
|
|
|
|
// CtxWithHandleTruncateErrLevel returns a new BuildContext with the specified level for handling truncate error.
|
|
func CtxWithHandleTruncateErrLevel(ctx BuildContext, level errctx.Level) BuildContext {
|
|
truncateAsWarnings, ignoreTruncate := false, false
|
|
switch level {
|
|
case errctx.LevelWarn:
|
|
truncateAsWarnings = true
|
|
case errctx.LevelIgnore:
|
|
ignoreTruncate = true
|
|
default:
|
|
}
|
|
|
|
evalCtx := ctx.GetEvalCtx()
|
|
tc, ec := evalCtx.TypeCtx(), evalCtx.ErrCtx()
|
|
|
|
flags := tc.Flags().
|
|
WithTruncateAsWarning(truncateAsWarnings).
|
|
WithIgnoreTruncateErr(ignoreTruncate)
|
|
|
|
if tc.Flags() == flags && ec.LevelForGroup(errctx.ErrGroupTruncate) == level {
|
|
// We do not need to create a new context if the flags and level are the same.
|
|
return ctx
|
|
}
|
|
|
|
return &innerOverrideBuildContext{
|
|
BuildContext: ctx,
|
|
evalCtx: &innerOverrideEvalContext{
|
|
EvalContext: evalCtx,
|
|
typeCtx: tc.WithFlags(flags),
|
|
errCtx: ec.WithErrGroupLevel(errctx.ErrGroupTruncate, level),
|
|
},
|
|
}
|
|
}
|
|
|
|
// AssertLocationWithSessionVars asserts the location in the context and session variables are the same.
|
|
// It is only used for testing.
|
|
func AssertLocationWithSessionVars(ctxLoc *time.Location, vars *variable.SessionVars) {
|
|
ctxLocStr := ctxLoc.String()
|
|
varsLocStr := vars.Location().String()
|
|
stmtLocStr := vars.StmtCtx.TimeZone().String()
|
|
intest.Assert(ctxLocStr == varsLocStr && ctxLocStr == stmtLocStr,
|
|
"location mismatch, ctxLoc: %s, varsLoc: %s, stmtLoc: %s",
|
|
ctxLocStr, varsLocStr, stmtLocStr,
|
|
)
|
|
}
|
|
|
|
// StaticConvertibleExprContext provides more methods to implement the clone of a `ExprContext`
|
|
type StaticConvertibleExprContext interface {
|
|
ExprContext
|
|
|
|
GetStaticConvertibleEvalContext() StaticConvertibleEvalContext
|
|
GetPlanCacheTracker() *contextutil.PlanCacheTracker
|
|
GetLastPlanColumnID() int64
|
|
}
|
|
|
|
// StaticConvertibleEvalContext provides more methods to implement the clone of a `EvalContext`
|
|
type StaticConvertibleEvalContext interface {
|
|
EvalContext
|
|
|
|
AllParamValues() []types.Datum
|
|
GetWarnHandler() contextutil.WarnHandler
|
|
}
|