Tim, thanks for the detailed response. One other poster had suggested I use the dollar only placeholder setting, but as you pointed out, DBIx::Class (I guess due to SQL::Abstract) is using ?, so I got errors about mixing the two. I'm happy to contribute any discussion on the ramifications, but if you could tell me where in the DBIx::Class code I to look, then we could try \? here. Thanks!
Augustus On Dec 19, 2014, at 2:40 AM, Tim Bunce <tim.bu...@pobox.com> wrote: > Hello Augustus. > > On Thu, Dec 04, 2014 at 03:38:14PM -0800, Augustus Saunders wrote: >> Hi all, I have been unable to find a way to use some of the new >> JSONB operators in Postgres 9.4 with DBIx::Class. A quick search >> for JSONB on the email archive site didn't turn up any results, so >> I thought I would ask. >> >> In particular, ?, ?&, and ?| are now operators, and we run into >> problems with the DBI placeholder being ?. > > As more people start using Postgres 9.4 and the JSON operators this > is going to become a significant problem. > >> I read that putting single quotes around the question mark would >> allow a literal question mark in DBI, but I can't seem to make this >> work from DBIx::Class. > > It won't do what you want. Question marks in quotes are ignored by the > DBI driver, but question marks in quotes won't work as JSON operators. > >> Can anybody tell me whether this is currently possible, if so how, >> and if not what might be involved or where in the code to look? > > For code not using DBIx::Class the pg_placeholder_dollaronly attribute > might work, see https://metacpan.org/pod/DBD::Pg#Placeholders > > For code using DBIx::Class the problem is more tricky. I'm pretty sure > that SQL::Abstract and thus DBIx::Class only support question mark > placeholders. That means it probably impossible to use expressions > containing a question mark operator with SQL::Abstract/DBIx::Class. > (Though I'd be delighted to be proven wrong.) > > So I think the DBI spec for placeholders needs to be extended to allow a > way to 'escape' a question mark that the driver would otherwise treat as > a placeholder. > > The obvious and natural approach would be to use a backslash before a > question mark. The backslash would be removed by the driver before the > statement is passed to the backend. > > $dbh->selectrow_array(q{ SELECT {"a":1, "b":2}'::jsonb ? 'b' }); # breaks > $dbh->selectrow_array(q{ SELECT {"a":1, "b":2}'::jsonb \? 'b' }); # would > work > > The key question is: what is the risk of any existing DBI SQL statements > containing a question mark placeholder that's preceeded by a backslash? > > Can anyone think of realistic examples? (For ANY DBI driver or backend.) > > Tim. > > _______________________________________________ > List: http://lists.scsys.co.uk/cgi-bin/mailman/listinfo/dbix-class > IRC: irc.perl.org#dbix-class > SVN: http://dev.catalyst.perl.org/repos/bast/DBIx-Class/ > Searchable Archive: http://www.grokbase.com/group/dbix-class@lists.scsys.co.uk _______________________________________________ List: http://lists.scsys.co.uk/cgi-bin/mailman/listinfo/dbix-class IRC: irc.perl.org#dbix-class SVN: http://dev.catalyst.perl.org/repos/bast/DBIx-Class/ Searchable Archive: http://www.grokbase.com/group/dbix-class@lists.scsys.co.uk
