SelectWithUnionQuery (children 1) ExpressionList (children 1) SelectQuery (children 2) ExpressionList (children 1) Asterisk TablesInSelectQuery (children 2) TablesInSelectQueryElement (children 1) TableExpression (children 1) TableIdentifier t TablesInSelectQueryElement (children 2) TableExpression (children 1) TableIdentifier s TableJoin (children 1) Function and (children 1) ExpressionList (children 2) Function equals (children 1) ExpressionList (children 2) Identifier t.a Identifier s.a Function equals (children 1) ExpressionList (children 2) Identifier t.b Identifier s.b