Documentation ¶
Index ¶
- Constants
- func ExplainColumnList(ctx sessionctx.Context, cols []*MPPPartitionColumn) []byte
- func GetCollateIDByNameForPartition(coll string) int32
- func GetCollateNameByIDForPartition(collateID int32) string
- func ToString(ndvs []GroupNDV) string
- type GroupNDV
- type LogicalProperty
- type MPPPartitionColumn
- type MPPPartitionType
- type PhysicalProperty
- func (p *PhysicalProperty) AllColsFromSchema(schema *expression.Schema) bool
- func (p *PhysicalProperty) AllSameOrder() (isSame bool, desc bool)
- func (p *PhysicalProperty) CloneEssentialFields() *PhysicalProperty
- func (p *PhysicalProperty) GetAllPossibleChildTaskTypes() []TaskType
- func (p *PhysicalProperty) HashCode() []byte
- func (p *PhysicalProperty) IsFlashProp() bool
- func (p *PhysicalProperty) IsPrefix(prop *PhysicalProperty) bool
- func (p *PhysicalProperty) IsSortItemAllForPartition() bool
- func (p *PhysicalProperty) IsSortItemEmpty() bool
- func (p *PhysicalProperty) IsSubsetOf(keys []*MPPPartitionColumn) []int
- func (p *PhysicalProperty) MemoryUsage() (sum int64)
- func (p *PhysicalProperty) String() string
- type SortItem
- type StatsInfo
- type TaskType
Constants ¶
const ( NoCTEOrAllProducerCanMPP cteProducerStatus = iota SomeCTEFailedMpp AllCTECanMpp )
Constants for CTE status.
Variables ¶
This section is empty.
Functions ¶
func ExplainColumnList ¶
func ExplainColumnList(ctx sessionctx.Context, cols []*MPPPartitionColumn) []byte
ExplainColumnList generates explain information for a list of columns.
func GetCollateIDByNameForPartition ¶
GetCollateIDByNameForPartition returns collate id by collation name
func GetCollateNameByIDForPartition ¶
GetCollateNameByIDForPartition returns collate id by collation name
Types ¶
type LogicalProperty ¶
type LogicalProperty struct { Stats *StatsInfo Schema *expression.Schema MaxOneRow bool }
LogicalProperty stands for logical properties such as schema of expression, or statistics of columns in schema for output of Group. All group expressions in a group share same logical property.
type MPPPartitionColumn ¶
type MPPPartitionColumn struct { Col *expression.Column CollateID int32 }
MPPPartitionColumn is the column that will be used in MPP Hash Exchange
func (*MPPPartitionColumn) Equal ¶
func (partitionCol *MPPPartitionColumn) Equal(other *MPPPartitionColumn) bool
Equal returns true if partitionCol == other
func (*MPPPartitionColumn) MemoryUsage ¶
func (partitionCol *MPPPartitionColumn) MemoryUsage() (sum int64)
MemoryUsage return the memory usage of MPPPartitionColumn
type MPPPartitionType ¶
type MPPPartitionType int
MPPPartitionType is the way to partition during mpp data exchanging.
const ( // AnyType will not require any special partition types. AnyType MPPPartitionType = iota // BroadcastType requires current task to broadcast its data. BroadcastType // HashType requires current task to shuffle its data according to some columns. HashType // SinglePartitionType requires all the task pass the data to one node (tidb/tiflash). SinglePartitionType )
func (MPPPartitionType) ToExchangeType ¶
func (t MPPPartitionType) ToExchangeType() tipb.ExchangeType
ToExchangeType generates ExchangeType from MPPPartitionType
type PhysicalProperty ¶
type PhysicalProperty struct { // SortItems contains the required sort attributes. SortItems []SortItem // TaskTp means the type of task that an operator requires. // // It needs to be specified because two different tasks can't be compared // with cost directly. e.g. If a copTask takes less cost than a rootTask, // we can't sure that we must choose the former one. Because the copTask // must be finished and increase its cost in sometime, but we can't make // sure the finishing time. So the best way to let the comparison fair is // to add TaskType to required property. TaskTp TaskType // ExpectedCnt means this operator may be closed after fetching ExpectedCnt // records. ExpectedCnt float64 // indicates that whether we are allowed to add an enforcer. CanAddEnforcer bool // If the partition type is hash, the data should be reshuffled by partition cols. MPPPartitionCols []*MPPPartitionColumn // which types the exchange sender belongs to, only take effects when it's a mpp task. MPPPartitionTp MPPPartitionType // SortItemsForPartition means these sort only need to sort the data of one partition, instead of global. // It is added only if it is used to sort the sharded data of the window function. // Non-MPP tasks do not care about it. SortItemsForPartition []SortItem // RejectSort means rejecting the sort property from its children, but it only works for MPP tasks. // Non-MPP tasks do not care about it. RejectSort bool CTEProducerStatus cteProducerStatus // contains filtered or unexported fields }
PhysicalProperty stands for the required physical property by parents. It contains the orders and the task types.
func NewPhysicalProperty ¶
func NewPhysicalProperty(taskTp TaskType, cols []*expression.Column, desc bool, expectCnt float64, enforced bool) *PhysicalProperty
NewPhysicalProperty builds property from columns.
func (*PhysicalProperty) AllColsFromSchema ¶
func (p *PhysicalProperty) AllColsFromSchema(schema *expression.Schema) bool
AllColsFromSchema checks whether all the columns needed by this physical property can be found in the given schema.
func (*PhysicalProperty) AllSameOrder ¶
func (p *PhysicalProperty) AllSameOrder() (isSame bool, desc bool)
AllSameOrder checks if all the items have same order.
func (*PhysicalProperty) CloneEssentialFields ¶
func (p *PhysicalProperty) CloneEssentialFields() *PhysicalProperty
CloneEssentialFields returns a copy of PhysicalProperty. We only copy the essential fields that really indicate the property, specifically, `CanAddEnforcer` should not be included.
func (*PhysicalProperty) GetAllPossibleChildTaskTypes ¶
func (p *PhysicalProperty) GetAllPossibleChildTaskTypes() []TaskType
GetAllPossibleChildTaskTypes enumrates the possible types of tasks for children.
func (*PhysicalProperty) HashCode ¶
func (p *PhysicalProperty) HashCode() []byte
HashCode calculates hash code for a PhysicalProperty object.
func (*PhysicalProperty) IsFlashProp ¶
func (p *PhysicalProperty) IsFlashProp() bool
IsFlashProp return true if this physical property is only allowed to generate flash related task
func (*PhysicalProperty) IsPrefix ¶
func (p *PhysicalProperty) IsPrefix(prop *PhysicalProperty) bool
IsPrefix checks whether the order property is the prefix of another.
func (*PhysicalProperty) IsSortItemAllForPartition ¶
func (p *PhysicalProperty) IsSortItemAllForPartition() bool
IsSortItemAllForPartition check whether SortItems is same as SortItemsForPartition
func (*PhysicalProperty) IsSortItemEmpty ¶
func (p *PhysicalProperty) IsSortItemEmpty() bool
IsSortItemEmpty checks whether the order property is empty.
func (*PhysicalProperty) IsSubsetOf ¶
func (p *PhysicalProperty) IsSubsetOf(keys []*MPPPartitionColumn) []int
IsSubsetOf check if the keys can match the needs of partition.
func (*PhysicalProperty) MemoryUsage ¶
func (p *PhysicalProperty) MemoryUsage() (sum int64)
MemoryUsage return the memory usage of PhysicalProperty
func (*PhysicalProperty) String ¶
func (p *PhysicalProperty) String() string
String implements fmt.Stringer interface. Just for test.
type SortItem ¶
type SortItem struct { Col *expression.Column Desc bool }
SortItem wraps the column and its order.
func SortItemsFromCols ¶
func SortItemsFromCols(cols []*expression.Column, desc bool) []SortItem
SortItemsFromCols builds property items from columns.
func (SortItem) MemoryUsage ¶
MemoryUsage return the memory usage of SortItem
type StatsInfo ¶
type StatsInfo struct { RowCount float64 // Column.UniqueID -> NDV ColNDVs map[int64]float64 HistColl *statistics.HistColl // StatsVersion indicates the statistics version of a table. // If the StatsInfo is calculated using the pseudo statistics on a table, StatsVersion will be PseudoVersion. StatsVersion uint64 // GroupNDVs stores the NDV of column groups. GroupNDVs []GroupNDV }
StatsInfo stores the basic information of statistics for the plan's output. It is used for cost estimation.
func (*StatsInfo) GetGroupNDV4Cols ¶
func (s *StatsInfo) GetGroupNDV4Cols(cols []*expression.Column) *GroupNDV
GetGroupNDV4Cols gets the GroupNDV for the given columns.
func (*StatsInfo) ScaleByExpectCnt ¶
ScaleByExpectCnt tries to Scale StatsInfo to an expectCnt which must be smaller than the derived cnt. TODO: try to use a better way to do this.
type TaskType ¶
type TaskType int
TaskType is the type of execution task.
const ( // RootTaskType stands for the tasks that executed in the TiDB layer. RootTaskType TaskType = iota // CopSingleReadTaskType stands for the a TableScan or IndexScan tasks // executed in the coprocessor layer. CopSingleReadTaskType // CopMultiReadTaskType stands for the a IndexLookup tasks executed in the // coprocessor layer. CopMultiReadTaskType // MppTaskType stands for task that would run on Mpp nodes, currently meaning the tiflash node. MppTaskType )