exprctx

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
}

type ConstantPropagateCheckContext struct {
	ExprContext
}

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)
}

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
}

type NullRejectCheckExprContext struct {
	ExprContext
}

type OptionalEvalPropDesc struct {
	// contains filtered or unexported fields
}

type OptionalEvalPropKey int

type OptionalEvalPropKeySet uint64

type OptionalEvalPropProvider interface {
	Desc() *OptionalEvalPropDesc
}

type ParamValues interface {
	// GetParamValue returns the value of the parameter by index.
	GetParamValue(idx int) (types.Datum, error)
}

type PlanColumnIDAllocator interface {
	// AllocPlanColumnID allocates column id for plan.
	AllocPlanColumnID() int64
	// GetLastPlanColumnID returns the last column id.
	GetLastPlanColumnID() int64
}

type SimplePlanColumnIDAllocator struct {
	// contains filtered or unexported fields
}

type StaticConvertibleEvalContext interface {
	EvalContext

	AllParamValues() []types.Datum
	GetWarnHandler() contextutil.WarnHandler
}

type StaticConvertibleExprContext interface {
	ExprContext

	GetStaticConvertibleEvalContext() StaticConvertibleEvalContext
	GetPlanCacheTracker() *contextutil.PlanCacheTracker
	GetLastPlanColumnID() int64
}