Re: CHAR vs VARCHAR

> I browsed the FAQ and mailing list briefly to try to garner information
> about the ups and downs of different character based datatypes. I did not
> see any good document on preference or when to use one over the other.
>
> http://postgresql.readysetnet.com/docs/faq-english.html#4.15 noted that
> some compression happens.
>
> http://postgresql.readysetnet.com/users-lounge/docs/7.0/user/datatype1066.htm
> gives a good description and notes that text is best choice, but it not
> being SQL compliant is an issue for most.
>
> The question is how much of speed difference is there between CHAR and
> VARCHAR when doing searches etc? or are there any good rules others use
> to determine when CHAR is better to use than VARCHAR or vice versa?

FAQ item is accurate that compression happens on all variable length
types.

--
Bruce Momjian | http://candle.pha.pa.us
pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 853-3000
+ If your life is a hard drive, | 830 Blythe Avenue
+ Christ can be your backup. | Drexel Hill, Pennsylvania 19026