func (this *builder) VisitUnionAll(node *algebra.UnionAll) (interface{}, error) {
this.order = nil // Disable aggregates from ORDER BY
this.delayProjection = false // Disable ORDER BY non-projected expressions
this.limit = nil
first, err := node.First().Accept(this)
if err != nil {
return nil, err
}
second, err := node.Second().Accept(this)
if err != nil {
return nil, err
}
this.maxParallelism = 0
return plan.NewUnionAll(first.(plan.Operator), second.(plan.Operator)), nil
}
func (this *builder) VisitUnion(node *algebra.Union) (interface{}, error) {
// Inject DISTINCT into both terms
distinct := this.distinct
this.distinct = true
defer func() { this.distinct = distinct }()
this.order = nil // Disable aggregates from ORDER BY
this.delayProjection = false // Disable ORDER BY non-projected expressions
this.limit = nil
first, err := node.First().Accept(this)
if err != nil {
return nil, err
}
second, err := node.Second().Accept(this)
if err != nil {
return nil, err
}
this.maxParallelism = 0
unionAll := plan.NewUnionAll(first.(plan.Operator), second.(plan.Operator))
return plan.NewSequence(unionAll, plan.NewDistinct()), nil
}