I see. Thanks for clarifying! Thom
2009/1/27 Richard Huxton <d...@archonet.com> > Thom Brown wrote: > > The reason I ask is because the documentation says "If character varying > is > > used without length specifier, the type accepts strings of any size. The > > latter is a PostgreSQL extension." I wasn't sure if such an extension > meant > > there was a level of over-head involved, or reduced its indexability. > > No - some other DBs might have different implementations (and so > restrictions) but varchar and text are basically interchangeable. They > are different types though, so if you add custom casts you might want to > do it for both. > > There is a limit on btree index size - about 2000 chars if I remember > correctly. That's because you need to fit three index values on an 8KB > page iirc (and there are overheads too). > > -- > Richard Huxton > Archonet Ltd >
