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PostgreSQL LISTEN / NOTIFY not working

Here is the basic setup:

  • The PHP script writes to a table in the database, and then returns it NOTIFY job_added. Then he begins to listen to the answer, releasingLISTEN job_complete

  • The daemon (written in C) has already released LISTEN jod_addedand therefore wakes up and processes the table.

  • The daemon processes the table and writes the results to the result table before calling NOTIFY job_complete

  • The PHP script then wakes up and extracts the result from the result table.

All but the last step works. The daemon uses libpq, and I checked the success NOTIFYreleased by the daemon after adding the result to the result table.

So, I think the problem is with the PHP script. Here is a sample code:

$id = query("INSERT into jobs_table (/* details not important */) VALUES (/* */) RETURNING id");

query("NOTIFY job_added");
//daemon wakes up and does its thing.

query("LISTEN job_complete".$id);

$time = time();
while((time() - $time) < 30) {
    $notify = pg_get_notify($conn);
    if($notify) {
        // Never gets here
        if($notify['message']=="job_complete".$id) {
            //our job has completed
            break;
        }
    }
    usleep(25000);
}

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+3
1

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Try:

 query('COMMIT');

, .

+1

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