SelectWithUnionQuery (children 1) ExpressionList (children 1) SelectQuery (children 3) ExpressionList (children 1) WithElement (children 1) Subquery (children 1) SelectWithUnionQuery (children 1) ExpressionList (children 1) SelectQuery (children 1) ExpressionList (children 1) Literal UInt64_1 (alias a) ExpressionList (children 1) QualifiedAsterisk (children 2) Identifier subquery_alias ColumnsTransformerList (children 1) ColumnsApplyTransformer TablesInSelectQuery (children 1) TablesInSelectQueryElement (children 1) TableExpression (children 1) TableIdentifier subquery (alias subquery_alias)