RE: anyway to determine # rows before fetch loop ends and without seperate count(*)

It doesn't work according to the DBI documentation.

>From _Programming the Perl DBI_, p. 223 (for example):

>For SELECT statements, execute simply "starts" the query within the
database engine. Use one of
>the fetch methods to retrieve the data after calling execute. The execute
method does _not_ return
>the number of rows that will be returned by the query (because most
databases can't tell in advance),
>it simply returns a true value.

If you are relying on that 'feature' you are asking for trouble.

There have been discussions over this issue on the list before.

-Will

-----Original Message-----
From: Rob Craig [mailto:rcraig@xxxxxxxxxxxxxxxxxxxx]
Sent: Wednesday 16 November 2005 17:19
To: listmail@xxxxxxxxxxxx
Cc: dbi-users@xxxxxxxx
Subject: Re: anyway to determine # rows before fetch loop ends and without
seperate count(*)


I am using DBD::mysql and I can get the number of rows by assigning the
result of the execute to a scalar:

my $rows = $sth->execute or die "Couldn't execute statement: " .
DBI->errstr;

maybe this doesn't work with DBD::Oracle?

Rob






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