Re: Concatenation containing a "null" term

> Is there a way of having the null-strings terms of the concatenation
> operator be considered as empty strings instead?

Use COALESCE.  Some people create a custom concatenation operator
that automatically does so.

http://www.postgresql.org/docs/8.1/interactive/functions-conditional.html#AEN12639
http://www.postgresql.org/docs/8.1/interactive/sql-createoperator.html