Hi,

I need to concat two or more strings, but found no help in the Dialect classes of Hibernate. I expected to find either a hibernate function concat() or perhaps a method on Dialect to which I could give a list of strings.
My problem is that the app is expected to run on both PostgresQL and MySQL which uses || and CONCAT respectively.

Could this be a new feature for hibernate, cross-db string concatenation?

Create function on PGSQL:

create function CONCAT(TEXT,TEXT) RETURNS TEXT AS'
BEGIN
RETURN $1 || $2;
END;
' language 'plpgsql';

Or concatinate strings in java code.

Hi baliukas,

Thnx for the answer - Im just wondering of the following would
fit your suggestion:

"from package.Object as o where o.uri = ? || name || '/' "

This works on PostgresQL and name is the name of a column.

"from package.Object as o where o.uri = CONCAT(?, name, '/')

..is the MySQL version.

Do you think this would on your pgsql function (aside it should take three parameters as to two)? Im mosly concerned about the name column.

It must work without problems, I am not sure, but it must be possible to make postgresql use index for this query with function help too. Just try it.

BTW The right way for this use case is to use query like this:

"from package.Object as o where o.domain = ? "