Tom Lane wrote: > Bruce Momjian <[EMAIL PROTECTED]> writes: > > Tom Lane wrote: > >> I'd say not. Can't we do some more refactoring and avoid so many > >> useless conversions? Seems like str_initcap is the wrong primitive API > >> --- the work ought to be done by a function that takes a char pointer > >> and a length. That would be a suitable basis for functions operating > >> on both text datums and C strings. > > > Yea, I thought about that idea too but it is going to add a strlen() > > calls in some places, but not in critical ones. > > Sure, but the cost-per-byte of the strlen should be a good bit less than > the cost-per-byte of the actual conversion, so that doesn't bother me > too much. > > Actually it seems like the hard part is not so much the input > representation as the output representation --- what should the > base-level initcap routine return, to be reasonably efficient for > both cases?
I hadn't gotten to trying it out yet, but I can see the output being a problem. You can't even really pre-allocate the storage before passing it because you don't know the length after case change. You could pass back a char* and repalloc to get the varlena header in there but that is very messy. Add to that that the multi-byte case also has to be converted to wide characters, so you have text -> char * -> wide chars -> char * -> text for the most complex case. I am starto to think that the simplest case is to keep the single-copy version in there for single-byte encodings and not worry about the overhead of the multi-byte case. -- Bruce Momjian <[EMAIL PROTECTED]> http://momjian.us EnterpriseDB http://enterprisedb.com + If your life is a hard drive, Christ can be your backup. + -- Sent via pgsql-patches mailing list (pgsql-patches@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-patches
