Re: [HACKERS] varchar() vs char16 performance

>
> I ran some timing tests to check the performance of varchar() vs char16.
> The results of the test indicate that there is no difference in
> performance (within the timing scatter of the tests):
>
> char16    vc(16)
>  0.99s     1.05s    1 row (this measures startup time, not types)
> 39.29s    39.28s    ~65000 rows
>
> The char2,4,8,16 types seem to have no value-added over the
> better-supported char(), varchar(), text types; I am considering
> removing them from the backend, and instead have the parser
> transparently translate the types into varchar() (or char() - I'm not
> certain which is a better match for the types) for v6.4. Applications
> would not have to be changed.

Fine, remove them.  You may want to keep 'char' because of the reduced
overhead compared to char(1), but the others certainly can be removed.
Seems like you have not mentioned char, so you may no intension of
removing it.

I would map to char().  They are fixed size, and the old types were
fixed size too.  I know char16 may be better for varchar(), but that is
not as clean a translation from the old type.

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