SelectWithUnionQuery (children 1) ExpressionList (children 1) SelectQuery (children 2) ExpressionList (children 1) Asterisk TablesInSelectQuery (children 2) TablesInSelectQueryElement (children 1) TableExpression (children 1) TableIdentifier t1 TablesInSelectQueryElement (children 2) TableExpression (children 1) TableIdentifier rdb TableJoin (children 1) Function equals (children 1) ExpressionList (children 2) Function plus (children 1) ExpressionList (children 2) Identifier rdb.key Literal UInt64_1 Identifier t1.k