The problem appears to be due to the use of an Oracle keyword as the column alias. The below query fails in sqlplus, also, unless I change the "cr.timeend AS date," to "cr.timeend AS mydate,".

Here is the cron output:

Running completion_criteria_activity->cron()
!!! Error reading from database !!!
!! ORA-00923: FROM keyword not found where expected

SELECT DISTINCT
c.id AS course,
cr.timeend AS date,
cr.id AS criteriaid,
ra.userid AS userid,
mc.timemodified AS timecompleted
FROM
m_course_completion_criteria cr
INNER JOIN
m_course c
ON cr.course = c.id
INNER JOIN
m_context con
ON con.instanceid = c.id
INNER JOIN
m_role_assignments ra
ON ra.contextid = con.id
INNER JOIN
m_course_modules_completion mc
ON mc.coursemoduleid = cr.moduleinstance
AND mc.userid = ra.userid
LEFT JOIN
m_course_completion_crit_compl cc
ON cc.criteriaid = cr.id
AND cc.userid = ra.userid
WHERE
cr.criteriatype = 4
AND con.contextlevel = 50
AND c.enablecompletion = 1
AND cc.id IS NULL
AND (
mc.completionstate = 1
OR mc.completionstate = 2
)

[array (
)] !!
!! Stack trace: * line 391 of /lib/dml/moodle_database.php: dml_read_exception thrown

• line 268 of /lib/dml/oci_native_moodle_database.php: call to moodle_database->query_end()
• line 1010 of /lib/dml/oci_native_moodle_database.php: call to oci_native_moodle_database->query_end()
• line 231 of /lib/completion/completion_criteria_activity.php: call to oci_native_moodle_database->get_recordset_sql()
• line 220 of /lib/completion/cron.php: call to completion_criteria_activity->cron()
• line 43 of /lib/completion/cron.php: call to completion_cron_criteria()
• line 198 of /lib/cronlib.php: call to completion_cron()
• line 79 of /admin/cron.php: call to cron_run()
  !!