Re: [Q] string to int hash function for small range

or do a mod 256 e.g.

mod(get_byte(md5(id),'hex'),256)

HTH
Martin
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> Date: Sat, 7 Mar 2009 19:23:25 -0800
> From: pierce(at)hogranch(dot)com
> To: toreason(at)fastmail(dot)fm
> CC: pgsql-general(at)postgresql(dot)org
> Subject: Re: [GENERAL] [Q] string to int hash function for small range
>
> V S P wrote:
> > I would like to have a function
> > given a user id varchar(64) to get a hash number between 0 and 255.
> >
> > I first tried md5 but the number it returns is very big and cannot
> > be converted to an INT
> >
> > there is likely a way to simply add ascii values of the userId together
> > to get a small integer, but wanted to know if there are any other
> > 'built-in' ways
> >
> > this is to get the database id based on user id.
> >
>
> maybe take the last byte (2 chars) of the md5, and convert to integer?
> something like....
>
>
> get_byte(decode(md5(id),'hex'),16)
>
>
>
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