func (b *executorBuilder) buildJoin(v *plan.PhysicalHashJoin) Executor {
var leftHashKey, rightHashKey []*expression.Column
var targetTypes []*types.FieldType
for _, eqCond := range v.EqualConditions {
ln, _ := eqCond.Args[0].(*expression.Column)
rn, _ := eqCond.Args[1].(*expression.Column)
leftHashKey = append(leftHashKey, ln)
rightHashKey = append(rightHashKey, rn)
targetTypes = append(targetTypes, types.NewFieldType(types.MergeFieldType(ln.GetType().Tp, rn.GetType().Tp)))
}
e := &HashJoinExec{
schema: v.GetSchema(),
otherFilter: expression.ComposeCNFCondition(v.OtherConditions),
prepared: false,
ctx: b.ctx,
targetTypes: targetTypes,
concurrency: v.Concurrency,
defaultValues: v.DefaultValues,
}
if v.SmallTable == 1 {
e.smallFilter = expression.ComposeCNFCondition(v.RightConditions)
e.bigFilter = expression.ComposeCNFCondition(v.LeftConditions)
e.smallHashKey = rightHashKey
e.bigHashKey = leftHashKey
e.leftSmall = false
} else {
e.leftSmall = true
e.smallFilter = expression.ComposeCNFCondition(v.LeftConditions)
e.bigFilter = expression.ComposeCNFCondition(v.RightConditions)
e.smallHashKey = leftHashKey
e.bigHashKey = rightHashKey
}
if v.JoinType == plan.LeftOuterJoin || v.JoinType == plan.RightOuterJoin {
e.outer = true
}
if e.leftSmall {
e.smallExec = b.build(v.GetChildByIndex(0))
e.bigExec = b.build(v.GetChildByIndex(1))
} else {
e.smallExec = b.build(v.GetChildByIndex(1))
e.bigExec = b.build(v.GetChildByIndex(0))
}
for i := 0; i < e.concurrency; i++ {
ctx := &hashJoinCtx{}
if e.bigFilter != nil {
ctx.bigFilter = e.bigFilter.Clone()
}
if e.otherFilter != nil {
ctx.otherFilter = e.otherFilter.Clone()
}
ctx.datumBuffer = make([]types.Datum, len(e.bigHashKey))
ctx.hashKeyBuffer = make([]byte, 0, 10000)
e.hashJoinContexts = append(e.hashJoinContexts, ctx)
}
return e
}
//TODO: select join algorithm during cbo phase.
func (b *executorBuilder) buildJoin(v *plan.PhysicalHashJoin) Executor {
var leftHashKey, rightHashKey []*expression.Column
var targetTypes []*types.FieldType
for _, eqCond := range v.EqualConditions {
ln, _ := eqCond.Args[0].(*expression.Column)
rn, _ := eqCond.Args[1].(*expression.Column)
leftHashKey = append(leftHashKey, ln)
rightHashKey = append(rightHashKey, rn)
targetTypes = append(targetTypes, types.NewFieldType(types.MergeFieldType(ln.GetType().Tp, rn.GetType().Tp)))
}
e := &HashJoinExec{
schema: v.GetSchema(),
otherFilter: expression.ComposeCNFCondition(v.OtherConditions),
prepared: false,
ctx: b.ctx,
targetTypes: targetTypes,
}
if v.SmallTable == 1 {
e.smallFilter = expression.ComposeCNFCondition(v.RightConditions)
e.bigFilter = expression.ComposeCNFCondition(v.LeftConditions)
e.smallHashKey = rightHashKey
e.bigHashKey = leftHashKey
e.leftSmall = false
} else {
e.leftSmall = true
e.smallFilter = expression.ComposeCNFCondition(v.LeftConditions)
e.bigFilter = expression.ComposeCNFCondition(v.RightConditions)
e.smallHashKey = leftHashKey
e.bigHashKey = rightHashKey
}
if v.JoinType == plan.LeftOuterJoin || v.JoinType == plan.RightOuterJoin {
e.outer = true
}
if e.leftSmall {
e.smallExec = b.build(v.GetChildByIndex(0))
e.bigExec = b.build(v.GetChildByIndex(1))
} else {
e.smallExec = b.build(v.GetChildByIndex(1))
e.bigExec = b.build(v.GetChildByIndex(0))
}
return e
}