issue #133: delete unique index (take 2)

db/install.xml

@@ -75,7 +75,6 @@
       </KEYS>
       <INDEXES>
         <INDEX NAME="coursemoduleid" UNIQUE="false" FIELDS="coursemoduleid" COMMENT="For quick access via course-module (e.g. when displaying course module settings page and we need to determine whether anyone has completed it)."/>
-        <INDEX NAME="userid-coursemoduleid" UNIQUE="true" FIELDS="userid, coursemoduleid"/>
       </INDEXES>
     </TABLE>
     <TABLE NAME="local_recompletion_qa" COMMENT="archive of quiz attempts table">

db/upgrade.php

@@ -973,5 +973,19 @@ function xmldb_local_recompletion_upgrade($oldversion) {
         upgrade_plugin_savepoint(true, 2023112100, 'local', 'recompletion');
     }
 
+    if ($oldversion < 2023112600) {
+        // Define table local_recompletion_cmv to be created.
+        $table = new xmldb_table('local_recompletion_cmv');
+        $index = new xmldb_index('userid-coursemoduleid', XMLDB_INDEX_UNIQUE, ['userid', 'coursemoduleid']);
+
+        // Conditionally launch drop index.
+        if ($dbman->index_exists($table, $index)) {
+            $dbman->drop_index($table, $index);
+        }
+
+        // Recompletion savepoint reached.
+        upgrade_plugin_savepoint(true, 2023112600, 'local', 'recompletion');
+    }
+
     return true;
 }

version.php

@@ -24,8 +24,8 @@
 
 defined('MOODLE_INTERNAL') || die;
 
-$plugin->version   = 2023112100;
-$plugin->release   = 2023112100;
+$plugin->version   = 2023112600;
+$plugin->release   = 2023112600;
 $plugin->maturity  = MATURITY_STABLE;
 $plugin->requires  = 2022112805; // Requires 4.1.
 $plugin->component = 'local_recompletion';