Hi all,

I am using DBIx::Class to work with DB. Works fine, the development is really quick. Now I need to lock a table - but don't know how. I didn't find any documentation or example on this. Is it possible?

I am trying to do something like this:

# lock Table here
my $obj_rs = $schema->resultset("Table")->search({ col1 => $val });
my $obj = $obj_rs->next;
my $old_val = $obj->col2;
my $new_val = maybe_expensive_computation($old_val);
$obj->col2($new_val);
$obj->update;
# ... fetch and update some more rows
# unlock Table here
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This code could be run in multiple processes in parallel. I need the maybe_expensive_computation() to be run by 1 process at most because it can be influenced by another process running the same function. If more than one process tries to do the computation, only one should "get in", others should wait.

I can solve all of this with hand-written SQL and DBI (LOCK, few SELECTs and UPDATEs, UNLOCK), but I'd rather use DBIx::Class.

So the question I'd like to ask: how to lock a table while accessing DB with DBIx::Class?

Thank you.

ico