MDL-13424 and MDL-14544: New function tag_cleanup removes unused un-official tags, or unlinked tags. Not yet called automatically. (merge from 1.9)

This commit is contained in:
scyrma 2008-04-30 07:37:34 +00:00
parent 62a0ae1064
commit 9545cdba72

View file

@ -680,6 +680,59 @@ function tag_autocomplete($text) {
return get_records_sql("SELECT tg.id, tg.name, tg.rawname FROM {$CFG->prefix}tag tg WHERE tg.name LIKE '". moodle_strtolower($text) ."%'");
}
/**
* Clean up the tag tables, making sure all tagged object still exists.
*
* This should normally not be necessary, but in case related tags are not deleted
* when the tagged record is removed, this should be done once in a while, perhaps on
* an occasional cron run. On a site with lots of tags, this could become an expensive
* function to call: don't run at peak time.
*/
function tag_cleanup() {
global $CFG;
$tags = get_records('tag');
$instances = get_records('tag_instance');
foreach($instances as $instance) {
$delete = false;
if(!array_key_exists($instance->tagid, $tags)) {
// if the tag has been removed, instance should be deleted.
$delete = true;
} else {
switch ($instance->itemtype) {
case 'user': // users are marked as deleted, but not actually deleted
if (record_exists('user', 'id', $instance->itemid, 'deleted', 1)) {
$delete = true;
}
break;
default: // anything else, if the instance is not there, delete.
if (!record_exists($instance->itemtype, 'id', $instance->itemid)) {
$delete = true;
}
break;
}
}
if ($delete) {
tag_delete_instance($instance->itemtype, $instance->itemid, $instance->tagid);
//debugging('deleting tag_instance #'. $instance->id .', linked to tag id #'. $instance->tagid, DEBUG_DEVELOPER);
}
}
// TODO: this will only clean tags of type 'default'. This is good as
// it won't delete 'official' tags, but the day we get more than two
// types, we need to fix this.
$tags = get_records('tag', 'tagtype', 'default'); // do it again - might be different now.
foreach($tags as $tag) {
if (!record_exists_sql("SELECT * FROM {$CFG->prefix}tag tg, {$CFG->prefix}tag_instance ti WHERE tg.id = {$tag->id} AND ti.tagid = tg.id")) {
tag_delete($tag->id);
//debugging('deleting tag #'. $tag->id, DEBUG_DEVELOPER);
}
}
}
/**
* Calculates and stores the correlated tags of all tags.
* The correlations are stored in the 'tag_correlation' table.