,--- You/Andres (Fri, 7 Oct 2011 02:28:30 +0200) ----*
| > a lot of cases where the database could deduce (quite easily) that a
| > result column cannot be null
| Could you quickly explain what exactly you want that information for? Just
| because it has been done before doesn't necessarily mean its a good idea...
I am not writing a database application here (i.e. I am not storing
the data). I am responding to a client requirement, basically:
Given a SELECT (or possibly, simpler, a table name), tell me which columns are non-nullable?
I can give the answer about the tables trivially in 'psql' (using
pg_attribute.attnotnull). But it has to be done inside the C code I
wrote a couple of years ago, already using libpq, preparing and
describing arbitrary statements... If I could get the required
information through some use of PQ* functions...
But, oh well, I'll "PQexec(a-fancy-select-from-pg_attribute)".
Ugly :(
-- Alex -- alex-goncharov@comcast.net --
