No other database issues that I'm aware of.
I've been looking at more php error logs and there are two distinct errors occurring over and over. One takes the form:
[11-Jul-2014 13:42:58 America/Vancouver] Default exception handler: Can not find data record in database table course. Debug: SELECT * FROM {course} WHERE id = ?
[array (
0 => 64995,
)]
Error code: invalidrecord
* line 1385 of \lib\dml\moodle_database.php: dml_missing_record_exception thrown
* line 1361 of \lib\dml\moodle_database.php: call to moodle_database->get_record_select()
* line 66 of \file.php: call to moodle_database->get_record()
The other:
[11-Jul-2014 13:37:27 America/Vancouver] Default exception handler: Can not find data record in database table context. Debug: SELECT * FROM {context} WHERE id = ?
[array (
0 => 1285,
)]
Error code: invalidrecord
* line 1385 of \lib\dml\moodle_database.php: dml_missing_record_exception thrown
* line 1361 of \lib\dml\moodle_database.php: call to moodle_database->get_record_select()
* line 5192 of \lib\accesslib.php: call to moodle_database->get_record()
* line 1377 of \lib\accesslib.php: call to context::instance_by_id()
* line 3724 of \lib\filelib.php: call to get_context_info_array()
* line 38 of \pluginfile.php: call to file_pluginfile()
The very strange thing is which tables the queries are running on. In the former, it's the course table, and in the latter, it's the context table. I can say definitively that the id's that are being searched for are mixed up. The 1285 above exists in the course table, and the 64995 exists in the context table. I also have confirmed that it's course 1285 that is (in this case) being looked for, and the item with context id 64995 that is being looked for.
How can it be that the code is looking in the incorrect table on one attempt, but then on a refresh looks in the correct table?
by Trevar Pearce.