SelectWithUnionQuery (children 1) ExpressionList (children 1) SelectQuery (children 1) ExpressionList (children 1) Function mapApply (children 1) ExpressionList (children 2) Function lambda (children 1) ExpressionList (children 2) Function tuple (children 1) ExpressionList (children 2) Identifier x Identifier y Identifier x Function map (children 1) ExpressionList (children 4) Literal UInt64_1 Literal UInt64_0 Literal UInt64_2 Literal UInt64_0