Re: checksum

Hi,

not sure I quite understand, but could you not just concatenate all the fields and test on that? like:

select test1, test2, test3 from testtable
where test1 || test2 || test3 = 'whateveryouwanttotest'

you might have to do some typecasting/conversion on data types other than strings...

regards Jonas:))

-----Original Message-----
From: Federico Balbi [mailto:fbalbi@cs.utsa.edu]
Sent: 26. september 2004 20:32
To: postgresql-general
Subject: Re: checksum


> David Helgason wrote:
>
> >>   I was wondering if PGSQL has a function similar to
> >> binary_checksum() of
> >> MS SQL Server 2000. It is pretty handy when it comes to compare rows of
> >> data instead of having to write long boolean expressions.
> >> binary_checksum() takes a list of fields and it returns an integer value
> >> which sumarize the row content.
> >
> >
> You could use the md5 function.... such as :
>
> select md5(foo) from bar where baz = 2;

Looks like md5() takes only a string. I need to pass alist of fields
instead. I was looking at the documentattion and I think I can write
soemthing like:

field1, field2, ..., fieldn = expr1, expr2, ..., exprn

This way one operator will check all the fields for equality.

Fed