Replacing SIZE with COUNT produces wrong result when the target entity has a composite id

[beikov]

Subqueries are not affected, but the transformation which uses group by and count is wrong. This does not seem to be handeled properly and some databases don't support COUNT DISTINCT of a tuple. Therefore we will have to use the CHR or CHAR function to produce an expression like

col1 || CHR(1) || col2 || CHR(1) || ...

Since the character with the ASCII value of 1 will probably not be part of any string and the ASCII value 0 is not allowed, this should do the job.

JPA 2.1 compliant way would be

col1 || FUNCTION('CHR', 1) || col2 || FUNCTION'(CHR', 1) || ...

Databases that support row value constructors or tuples with a syntax like (col1, col2, ...) in count distincts could actually make use of it.

[beikov]

Right now we don't do count distinct in SizeSelectToCountTransformer so it seems this does not affect us anymore.

[beikov]

We currently only do count distinct in the count query of a paginated criteria builder. If the id of an entity really is an embedded id, this won't work.

[beikov]

Since this issue is not valid anymore, we close it.