Assistance required debugging 4.1-beta2-30532 wp-db.php problem

[dfavor]

Someone tell me the correct way to log all queries to debug.log as they execute, so I can debug this...

Thanks.
_

[24-Nov-2014 13:51:13 UTC] PHP Warning:  mysqli_fetch_object() expects parameter 1 to be mysqli_result, boolean given in /cluster/vhost/fastseohosting.com/wordpress/wp-includes/wp-db.php on line 1677
[24-Nov-2014 13:51:13 UTC] PHP Stack trace:
[24-Nov-2014 13:51:13 UTC] PHP   1. {main}() /cluster/vhost/fastseohosting.com/wordpress/wp-admin/admin-ajax.php:0
[24-Nov-2014 13:51:13 UTC] PHP   2. require_once() /cluster/vhost/fastseohosting.com/wordpress/wp-admin/admin-ajax.php:22
[24-Nov-2014 13:51:13 UTC] PHP   3. require_once() /cluster/vhost/fastseohosting.com/wordpress/wp-load.php:29
[24-Nov-2014 13:51:13 UTC] PHP   4. require_once() /cluster/vhost/fastseohosting.com/wordpress/wp-config.php:88
[24-Nov-2014 13:51:13 UTC] PHP   5. require_wp_db() /cluster/vhost/fastseohosting.com/wordpress/wp-settings.php:79
[24-Nov-2014 13:51:13 UTC] PHP   6. wpdb->__construct() /cluster/vhost/fastseohosting.com/wordpress/wp-includes/load.php:352
[24-Nov-2014 13:51:13 UTC] PHP   7. wpdb->db_connect() /cluster/vhost/fastseohosting.com/wordpress/wp-includes/wp-db.php:647
[24-Nov-2014 13:51:13 UTC] PHP   8. wpdb->set_sql_mode() /cluster/vhost/fastseohosting.com/wordpress/wp-includes/wp-db.php:1487
[24-Nov-2014 13:51:13 UTC] PHP   9. wpdb->query() /cluster/vhost/fastseohosting.com/wordpress/wp-includes/wp-db.php:831
[24-Nov-2014 13:51:13 UTC] PHP  10. mysqli_fetch_object() /cluster/vhost/fastseohosting.com/wordpress/wp-includes/wp-db.php:1677

[dfavor]

All plugins turned off. Twenty Fifteen active.

[dfavor]

Hum... seems like I found the place to insert debug code.

Offending query seems to be...

query   : SELECT option_value FROM wp_options WHERE option_name = '_transient_dash_4077549d03da2e451c8b5f002294ff51' LIMIT 1

Checking ​http://$site/wp-admin/options.php this transient does exist, so I'm unsure why the error is being thrown.

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[dfavor]

Hum... Looks like this error is being thrown for many query sets.

[pento]

Hi dfavor!

Going by the stack trace you posted, this seems to have happened when the DB first connected, and tried to set the sql_mode.

In your query log, could you please find the full query that starts with this?

SET SESSION sql_mode=

Also, what version of MySQL are you running?

[johnbillion]

dfavor, can you let us know the answer to Pento's question above please?

[pento]

Duplicate of #27982.

No need for feedback, this was fixed by [30677].