"Pierre Thibaudeau" <pierdeux@xxxxxxxxx> writes: > I am puzzling over this issue: > 1) Is there ever ANY reason to prefer "varchar(n)" to "text" as a column type? In words of one syllable: no. Not unless you have an application requirement for a specific maximum length limit (eg, your client code will crash if fed a string longer than 256 bytes, or there's a genuine data-validity constraint that you can enforce this way). Or if you want to have schema-level portability to some other DB that understands varchar(N) but not text. (varchar(N) is SQL-standard, while text isn't, so I'm sure there are some such out there.) > From my reading of the dataype documentation, the ONLY reason I can > think of for using "varchar(n)" would be in order to add an extra > data-type constraint to the column. That is *exactly* what it does. No more and no less. There's no performance advantage, in fact you can expect to lose a few cycles to the constraint check. regards, tom lane
