SelectWithUnionQuery (children 1) ExpressionList (children 1) SelectQuery (children 3) ExpressionList (children 1) Function mapConcat (children 1) ExpressionList (children 3) Identifier col Function map (children 1) ExpressionList (children 2) Literal \'key5\' Literal UInt64_500 Function map (children 1) ExpressionList (children 2) Literal \'key6\' Literal UInt64_600 TablesInSelectQuery (children 1) TablesInSelectQueryElement (children 1) TableExpression (children 1) TableIdentifier table_map ExpressionList (children 1) OrderByElement (children 1) Identifier id