Use consistent ordering in plans, blog blocks

If there are multiple blog posts or tasks with exactly the same
creation or completion time, the same blog post can appear on two
different pages of results, because the the order by part of the query
is not restrictive enough to produce an unambiguous order.

Change-Id: I59a7110b49e92af1a05dba37379707ea9fc225ef
Signed-off-by: Richard Mansfield <richard.mansfield@catalyst.net.nz>

htdocs/artefact/blog/blocktype/recentposts/lib.php

@@ -66,7 +66,7 @@ class PluginBlocktypeRecentposts extends PluginBlocktype {
                 AND a.parent IN ( ' . $artefactids . ' )
                 AND a.owner = (SELECT "owner" from {view} WHERE id = ?)
                 AND ' . $before . '
-                ORDER BY a.ctime DESC
+                ORDER BY a.ctime DESC, a.id DESC
                 LIMIT ' . $limit, array($instance->get('view')))) {
                 $mostrecent = array();
             }

htdocs/artefact/blog/blocktype/taggedposts/lib.php

@@ -65,7 +65,7 @@ class PluginBlocktypeTaggedposts extends SystemBlocktype {
                 WHERE a.artefacttype = \'blogpost\'
                 AND a.owner = (SELECT "owner" from {view} WHERE id = ?)
                 AND at.tag = ?
-                ORDER BY a.ctime DESC
+                ORDER BY a.ctime DESC, a.id DESC
                 LIMIT ?';
 
             $results = get_records_sql_array($sql, array($view, $tagselect, $limit));

htdocs/artefact/blog/lib.php

@@ -693,7 +693,7 @@ class ArtefactTypeBlogPost extends ArtefactType {
                 a.id, a.title, a.description, a.author, a.authorname, ' .
                 db_format_tsfield('a.ctime', 'ctime') . ', ' . db_format_tsfield('a.mtime', 'mtime') . ',
                 a.locked, bp.published, a.allowcomments ' . $from . '
-            ORDER BY bp.published ASC, a.ctime DESC',
+            ORDER BY bp.published ASC, a.ctime DESC, a.id DESC',
             array($id),
             $offset, $limit
         );

htdocs/artefact/plans/lib.php

@@ -533,7 +533,7 @@ class ArtefactTypeTask extends ArtefactType {
                 FROM {artefact} a
             JOIN {artefact_plans_task} at ON at.artefact = a.id
             WHERE a.artefacttype = 'task' AND a.parent = ?
-            ORDER BY at.completiondate ASC", array($plan), $offset, $limit))
+            ORDER BY at.completiondate ASC, a.id", array($plan), $offset, $limit))
             || ($results = array());
 
         // format the date and setup completed for display if task is incomplete