- But this approach is not guaranteed to work in all situations, and
- it is not strictly SQL-conforming. A future version of PostgreSQL
- might provide an additional feature to control the order in a
- better-defined way (<literal>xmlagg(expr ORDER BY expr, expr,
- ...</literal>).
+ But this syntax is not allowed in the SQL standard, and is
+ not portable to other database systems. A future version of
+ <productname>PostgreSQL</> might provide an additional feature to control
+ the order in a better-defined way (<literal>xmlagg(expr ORDER BY expr, expr,
+ ...)</literal>).