Bill Moseley wrote: > > > On Wed, May 12, 2010 at 1:08 AM, Peter Rabbitson <[email protected] > <mailto:rabbit%[email protected]>> wrote: > > Bill Moseley wrote: > > > > Is this the "blanket increment/decrement" that's referring to? > > > > sqlite> update track set pos = pos - 1 where cd = 1 and pos > 2; > > > > No need for where conds and the like. The most minimal test case is > to create a table with 1 column, with a unique constraint, and put > in the numbers 1..5. Then try: > > UPDATE tab SET col = col + 1; > > > and > > UPDATE tab SET col = col - 1; > > On sqlite (at least) on of these fails. Not sure for other databases, > never had the time to test. > > > > Seems to be the + 1 version. > > Postgresql has same "problem." > > Most of us work in just one or two databases, so indeed hard to test. > That's why I was asking about a flag so users can tell dbic the > approach to use.
Right, and once I get a list of which RDBMS can do what (or at least a start of such a list) I can add a capability flag to the Storage layer, and query that. _______________________________________________ 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/[email protected]
