Re: [PHP] LOCKS???
- Date: Mon, 28 Nov 2016 10:44:35 -0500
- From: Joshua Kehn <josh@xxxxxxx>
- Subject: Re: [PHP] LOCKS???
On Mon, Nov 28, 2016 at 10:19 AM, Tedd Sperling <tedd.sperling@xxxxxxxxx>
> To restate the current problem.
> I have two scripts accessed by two different computers (thus with
> different session ID’s).
> a) Computer One runs the first script which executes a LOCK --
> $query = "LOCK TABLES $table WRITE”;
> — and then writes to the table. This is confirmed by inspecting the table
> via phpMyAdmin.
> b) Computer two then runs the second script which only executes an UPDATE
> $query = "UPDATE $table SET i='$i' WHERE id=1 “;
> — and the value of i in $table is changed. This is also confirmed by
> inspecting the table via phpMyAdmin.
> This experiment demonstrates that LOCK TABLES does not work for me.
Are you using a transaction on “Computer One?”
If a session begins a transaction (for example, with START TRANSACTION), an
> implicit UNLOCK TABLES is performed, which causes existing locks to be
> released. (For additional information about the interaction between table
> locking and transactions, see Section 18.104.22.168, “Interaction of Table
> Locking and Transactions”.)
It could also be a question of whether the connection is being recreated
between when you issue the LOCK and when you do whatever work.
If the connection for a client session terminates, whether normally or
> abnormally, the server implicitly releases all table locks held by the
> session (transactional and nontransactional).
Both the above are from:
I'd encourage you to test the functionality you're expecting from a MySQL
prompt instead of another language to confirm if you're operating with the
correct queries or if the problem lays in the interface layer.