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.

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