I have been using perl to read and write to various tables in MySQL. However, when I try and lock the tables so that noone else can write while the table is being written to, I prevent all threads from being able to write to the table.

I think it has to do with how I am using perl to access the database. What is the best way to lock the tables, write/update the tables and then unlock. I only need to lock for write access, not read access.

Reading up on MySQL.com indicates the proper procedure, however, I may have my perl code in correct. Below is a snipett of my perl DB code without locking th talbes:

Use the below to open the db.

sub open_dbi {
   my $db_user = $DBuser;
   my $db_password = $DBpassword;
   my $DBName = 'db';
   my $dbh = DSBI->connect("dbi:mysql:DBName:$IP","$db_user","db_passw
+ord";
   return $dbh;
}

This part writes the sql command to the table:

sub write_db {
   $SQLCommand = "{SQL command}";
   my $sth = $dbh->prepare("$SQLCommand");
   $sth->execute;
}

[download]
How do I properly integrate the locking of tables for write access when I am performing the write_db() routine?

Please advise,
Simon

In reply to Using perl to lock the tables in mysql by sdyates

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