Re^3: Replacement for/working version of CGI::App::Plugin::BREAD ???

Thanks for the tip. I found an obscure reference to fetchrow_arrayref where the person was getting the same error I was, but couldn't figure out why. The reply was something to the effect that fetchrow_arrayref has "issues," and to not use it.

So I changed it to fetchrow_hashref (which is the version I normally used, anyway). I did the copy/paste routine with the code I was using until I figured out what it was really doing.

Anyway, what I discovered is that:

        my $sth2 = $dbh->prepare("SHOW FULL COLUMNS IN ?") or die 'pre
+pare failed';
        $sth2->execute($table) or die 'execute failed [' . $sth2->err 
+. '] [' . $sth2->errstr . ']';
[download]

dies with a syntax error. And that:

        my $sth2 = $dbh->prepare("SHOW FULL COLUMNS IN $table") or die
+ 'prepare failed';
        $sth2->execute() or die 'execute failed [' . $sth2->err . '] [
+' . $sth2->errstr . ']';
[download]

does not die, but also does not return any rows of data.

Lee Crites
lee@critesclan.com

Comment on Re^3: Replacement for/working version of CGI::App::Plugin::BREAD ??? Select or Download Code

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Re^4: Replacement for/working version of CGI::App::Plugin::BREAD ??? by Corion (Patriarch) on Jun 18, 2013 at 18:11 UTC
If you want to keep using placeholders, consider the Catalog Methods of DBI.	[reply]
Re^4: Replacement for/working version of CGI::App::Plugin::BREAD ??? by poj (Abbot) on Jun 18, 2013 at 17:39 UTC
No, you can't use a placeholder for a table name - see recent node DBI order by clause and placeholders. This works for me on MySQL `$dbh->prepare("SHOW FULL COLUMNS IN $table")` How are you retrieving records ? poj	[reply] [d/l]
Re^5: Replacement for/working version of CGI::App::Plugin::BREAD ??? by lee_crites (Scribe) on Jun 18, 2013 at 18:33 UTC
After working through a number of typos, I am getting closer. I agree, however, that the command works perfectly in MySQL. The issue is translating it to a DBI command. For my test, the MySQL command returns: `mysql> show columns in cmsParms; +--------+-----------+------+-----+---------+-------+ \| Field \| Type \| Null \| Key \| Default \| Extra \| +--------+-----------+------+-----+---------+-------+ \| pKey \| char(100) \| NO \| PRI \| NULL \| \| \| pValue \| text \| NO \| \| NULL \| \| +--------+-----------+------+-----+---------+-------+ 2 rows in set (0.00 sec)` [download] From inside my code: `my $rval = 'rval (' . $table . ')'; my $sth2 = $dbh->prepare("SHOW COLUMNS IN $table where Field=?") or die 'prepare failed'; $sth2->execute( $field ) or die 'execute failed'; if ( $sth2->err ) { $rval .= 'error: [' . $sth2->errmsg . ']'; } else { $rval .= '(' . $sth2->rows . ')'; my ($arr, @arr, %arr, $field); while ( $arr = $sth2->fetchrow_hashref ) { foreach $field ( keys %{ $arr } ) { $rval .= "[".$field.":".$arr->{ $field }."]"; } } } return($rval);` [download] What now is returned ($rval) is: `[rval (cmsParms)(1)[Extra:][Type:char(100)][Field:pKey][Default:][Null +:NO][Key:PRI]]` [download] This is exactly what I expected! Changes I made: I fixed a couple of (important) typos. I added "where Field=?" to the prepare, and $field in the execute, so it only returns the info for the one entry. Thanks for your help! Lee Crites lee@critesclan.com	[reply] [d/l] [select]