On 11/19/2012 09:43 PM, Stephen Frost wrote: > * Tom Lane (t...@sss.pgh.pa.us) wrote: >> Let me be clear here: I don't think we can or should ever make this >> into an error by default. Doing that would break spec-compliant >> applications, whether or not they are using names that actually have >> any conflicts. > > If we increase the length to the spec requirement (full disclosure- I > havn't checked the spec on this myself), I'd be for making it an error > if someone goes over that limit. Right now we have a risk of spec > compliant applications not working under PG for nearly zero good > justification in today's age (iow- I don't really buy the concern about > the size, and if that is a reasonable concern then we could look at > putting in the effort to make it variable length and seriously reduce > today's wasted space). Wasted space is only part of the issue; it's also potentially significantly cheaper to compare and copy fixed length names, especially when you can copy on-stack arrays rather than palloc'ing memory.
I have not checked to see whether this is a concern in Pg's codebase; I'm just aware it's been a reason for the use of fixed length strings in software in general. -- Craig Ringer http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services
