Re: Pearls (not really) of Perl programming

One of mine, in the early days of learning about DBI...

open INFILE, '<source.txt';

while (<INFILE>) {
   my $dbh = DBI->connect("dbi:mysql:database=maindb;host=localhost");
   my $sth = $dbh->prepare("SELECT * FROM $table WHERE uid=$user");
   $sth->execute;
   print join(',', $sth->fetchrow_array);
   print "\n";
}
[download]

Note the complete lack of error handling, no use of prototypes, and the assumption that only one row would be returned. I also particularly enjoy the two separate print statements. And, I printed to STDOUT (without setting $|) even though I wanted to write to a file.

radiantmatrix
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Perl is

Comment on Re: Pearls (not really) of Perl programming Download Code

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Re^2: Pearls (not really) of Perl programming by hubb0r (Pilgrim) on Nov 25, 2004 at 07:00 UTC
Plus, depending on the number of lines in the INFILE, you probably swamped the DB by not keeping the $dbh outside of the while.	[reply]
Re^3: Pearls (not really) of Perl programming by radiantmatrix (Parson) on Nov 25, 2004 at 13:43 UTC
Quite. Not to mention that particular app connected to a mysql instance that was about 5 router hops away over not-the-fastests links. Connect times averaged 5s, which really reared its ugly head when the input file was 2_000 lines. ;-) radiantmatrix `require General::Disclaimer;` Perl is	[reply]
Re^2: Pearls (not really) of Perl programming by ihb (Deacon) on Nov 26, 2004 at 02:17 UTC
Also, there's no `local`ization of the filehandle. `ihb` See perltoc if you don't know which perldoc to read! Read argumentation in its context!	[reply] [d/l]
Re^2: Pearls (not really) of Perl programming by Mr. Muskrat (Canon) on Dec 04, 2004 at 04:05 UTC
I could probably write a book on the subject of the OP but I'll stick to just one DBI example. `my $dbh = DBI->connect($database, $user, $password) or die $dbh->errstr;` When I found it, I decided to grep for it. It was being used in every script that pulled from the database!	[reply] [d/l]


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