Re: Comparing two tables of different database

Hi All, <br /><br />  For example, <br /><br />    There are two database.   database1 and database 2;<br />    <br
/>    database1 has a table called pr_1 with the columns, id,name and time.<br />     database2 has a table called sr_1
withthe_columns id,name and time.<br />    <br />     i would like to find out the differences that is, find the names
thatare not in sr_1 but in pr_1.<br />     we can achieve this by the query, <br />   <br />         select name from
sr_1where name not in (select name from pr_1);<br />     the above query will work in case of two tables in the same
database.<br/><br /><br />     But the problem is, these two tables are in different database. i did not understand
aboutthe dblink.<br /><br />    is there any exaples on dblink. can we do it without using dblink.<br /><br />-Nicholas
I<br/>    <br />      <br /><br /><div class="gmail_quote">On Thu, Apr 30, 2009 at 9:07 AM, Joshua Tolley <span
dir="ltr"><<ahref="mailto:eggyknap@gmail.com">eggyknap@gmail.com</a>></span> wrote:<br /><blockquote
class="gmail_quote"style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left:
1ex;"><divclass="im">On Thu, Apr 30, 2009 at 08:20:02AM +1000, Adam Ruth wrote:<br /> >    The simple answer is to
pg_dumpboth tables and compare the output with<br /> >    diff.<br /> >    Other than that, I think you'll need a
customprogram.<br /><br /></div>For all but the strictest definition of "identical", that won't work.<br /> Tables may
easilycontain the same information, in different on-disk<br /> order, and pg_dump will most likely give the data to you
inan order<br /> similar to its ordering on disk.<br /><br /> Something like a COPY (<query>) TO <file>,
where<query> includes an<br /> ORDER BY clause, might give you a suitable result from both tables, on<br /> which
youcould then take a checksum.<br /><br /> - Josh / eggyknap<br /><br />-----BEGIN PGP SIGNATURE-----<br /> Version:
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