func (this *builder) VisitIndexNest(node *algebra.IndexNest) (interface{}, error) {
_, err := node.Left().Accept(this)
if err != nil {
return nil, err
}
right := node.Right()
right.SetDefaultNamespace(this.namespace)
namespace, err := this.datastore.NamespaceByName(right.Namespace())
if err != nil {
return nil, err
}
keyspace, err := namespace.KeyspaceByName(right.Keyspace())
if err != nil {
return nil, err
}
nest, err := this.buildIndexNest(keyspace, node)
if err != nil {
return nil, err
}
this.subChildren = append(this.subChildren, nest)
return nil, nil
}
func (this *builder) buildIndexNest(keyspace datastore.Keyspace,
node *algebra.IndexNest) (op *plan.IndexNest, err error) {
index, covers, err := this.buildJoinScan(keyspace, node.Right(), "nest")
if err != nil {
return nil, err
}
return plan.NewIndexNest(keyspace, node, index, covers), nil
}
func NewIndexNest(keyspace datastore.Keyspace, nest *algebra.IndexNest,
index datastore.Index, covers expression.Covers) *IndexNest {
rv := &IndexNest{
keyspace: keyspace,
term: nest.Right(),
outer: nest.Outer(),
keyFor: nest.For(),
index: index,
covers: covers,
}
rv.idExpr = expression.NewField(
expression.NewMeta(expression.NewIdentifier(rv.keyFor)),
expression.NewFieldName("id", false))
return rv
}