func (b *executorBuilder) buildSelection(v *plan.Selection) Executor {
child := v.GetChildByIndex(0)
oldConditions := v.Conditions
var src Executor
switch x := child.(type) {
case *plan.PhysicalTableScan:
if x.LimitCount == nil {
src = b.buildNewTableScan(x, v)
} else {
src = b.buildNewTableScan(x, nil)
}
case *plan.PhysicalIndexScan:
if x.LimitCount == nil {
src = b.buildNewIndexScan(x, v)
} else {
src = b.buildNewIndexScan(x, nil)
}
default:
src = b.build(x)
}
if len(v.Conditions) == 0 {
v.Conditions = oldConditions
return src
}
exec := &SelectionExec{
Src: src,
Condition: expression.ComposeCNFCondition(v.Conditions),
schema: v.GetSchema(),
ctx: b.ctx,
}
v.Conditions = oldConditions
return exec
}
