Re: How do i compare 2 postgresql instanses ?

Hello there. Simple counts can certainly prove two databases are not the
same version. But what if you actually want to look at the data? I have been
thinking about row checksums, would you say this would be a reasonable way
of verifying two databases are equivalent? I have many other things on my
mind, so I haven't tried implementing this yet.

Michael

> you could write a little program (awk) to produce an sql file of the form:
> select count(*) from airlines;
> select count(*) from airports;
> select count(*) from airticket;
> select count(*) from airticketflights;
> ....
> select count(*) from zzzobjects;
>
> and then run it against the two databases, and diff the outputs.
> If the outputs are not identical then you have 2 different databases,
> otherwise you have to search more to know the answer.
> So this technique can prove that yours DBs are *not* identical, but does
> not say anything
> about the opposite.
>
> --
> Achilleas Mantzios
>
>