SelectWithUnionQuery (children 1) ExpressionList (children 1) SelectQuery (children 4) ExpressionList (children 1) Asterisk TablesInSelectQuery (children 2) TablesInSelectQueryElement (children 1) TableExpression (children 1) TableIdentifier t1 TablesInSelectQueryElement (children 2) TableExpression (children 1) TableIdentifier t2 TableJoin (children 1) Function and (children 1) ExpressionList (children 2) Function equals (children 1) ExpressionList (children 2) Identifier t1.time Identifier t2.time Literal NULL ExpressionList (children 1) OrderByElement (children 1) Identifier ALL Set