Tom Lane writes:
> A considerable advantage of per-relation constraint names is that a new
> unique name can be assigned for a nameless constraint while holding only
> a lock on the target relation. We'd need a global lock to create unique
> constraint names in the SQL92 semantics.
Presumably, the field pg_class.relchecks already keeps a count of the
number of constraints, so it should be possible to assign numbers easily.
> The only way I can see around that would be to use newoid(), or perhaps
> a dedicated sequence generator, to construct constraint names. The
> resulting unpredictable constraint names would be horribly messy to deal
> with in the regression tests, so I'm not eager to do this.
Or we simply assign constraint names explicitly in the regression tests.
--
Peter Eisentraut peter_e@gmx.net