diff --git a/application/config/version.php b/application/config/version.php
index b5a0dfef1d4..37d7689cdcc 100644
--- a/application/config/version.php
+++ b/application/config/version.php
@@ -12,7 +12,7 @@
  */
 
 $config['versionnumber'] = '5.2.0-dev';
-$config['dbversionnumber'] = 474;
+$config['dbversionnumber'] = 475;
 $config['buildnumber'] = '';
 $config['updatable'] = true;
 $config['templateapiversion']  = 3;
diff --git a/application/helpers/update/updatedb_helper.php b/application/helpers/update/updatedb_helper.php
index 112819c6e0a..91a6f35dcbe 100644
--- a/application/helpers/update/updatedb_helper.php
+++ b/application/helpers/update/updatedb_helper.php
@@ -3161,48 +3161,6 @@ function db_upgrade_all($iOldDBVersion, $bSilent = false)
             $oDB->createCommand()->createIndex('{{answers_idx}}', '{{answers}}', ['qid', 'code', 'scale_id'], true);
             $oDB->createCommand()->createIndex('{{answers_idx2}}', '{{answers}}', 'sortorder', false);
 
-            /**
-             * Regenerate codes for problematic label sets
-             * Helper function (TODO: Put in separate class)
-             * Fails silently
-             *
-             * @param int $lid Label set id
-             * @return void
-             */
-            $regenerateCodes = function (int $lid) {
-                $oDB = Yii::app()->getDb();
-
-                $labelSet = $oDB->createCommand(
-                    sprintf("SELECT * FROM {{labelsets}} WHERE lid = %d", (int) $lid)
-                )->queryRow();
-                if (empty($labelSet)) {
-                    return;
-                }
-
-                foreach (explode(',', $labelSet['languages']) as $lang) {
-                    $labels = $oDB->createCommand(
-                        sprintf(
-                            "SELECT * FROM {{labels}} WHERE lid = %d AND language = %s",
-                            (int) $lid,
-                            $oDB->quoteValue($lang)
-                        )
-                    )->queryAll();
-                    if (empty($labels)) {
-                        continue;
-                    }
-                    foreach ($labels as $key => $label) {
-                        $oDB->createCommand(
-                            sprintf(
-                                "UPDATE {{labels}} SET code = %s WHERE id = %d",
-                                // Use simply nr as label code
-                                $oDB->quoteValue((string) $key + 1),
-                                $label['id']
-                            )
-                        )->execute();
-                    }
-                }
-            };
-
             // Apply integrity fix before starting label set update.
             // List of label set ids which contain code duplicates.
             $lids = $oDB->createCommand(
@@ -3212,7 +3170,7 @@ function db_upgrade_all($iOldDBVersion, $bSilent = false)
                 HAVING COUNT(DISTINCT({{labels}}.code)) < COUNT({{labels}}.id)"
             )->queryAll();
             foreach ($lids as $lid) {
-                $regenerateCodes($lid['lid']);
+                regenerateLabelCodes400($lid['lid']);
             }
 
             // Labels table
@@ -4973,20 +4931,22 @@ function ($v) {
             $oDB->createCommand()->update('{{settings_global}}', array('stg_value' => 473), "stg_name='DBVersion'");
             $oTransaction->commit();
         }
-
-        if ($iOldDBVersion < 474) {
+        // 474 was left out for technical reasons
+        if ($iOldDBVersion < 475) {
             $oTransaction = $oDB->beginTransaction();
-            $aDefaultSurveyMenuEntries = LsDefaultDataSets::getSurveyMenuEntryData();
-            foreach ($aDefaultSurveyMenuEntries as $aSurveymenuentry) {
-                if ($aSurveymenuentry['name'] == 'listQuestionGroups') {
-                    if (SurveymenuEntries::model()->findByAttributes(['name' => $aSurveymenuentry['name']]) == null) {
-                        $oDB->createCommand()->insert('{{surveymenu_entries}}', $aSurveymenuentry);
-                        SurveymenuEntries::reorderMenu(2);
-                    }
-                    break;
-                }
+            // Apply integrity fix before adding unique constraint.
+            // List of label set ids which contain code duplicates.
+            $lids = $oDB->createCommand(
+                "SELECT lime_labels.lid AS lid
+                FROM lime_labels
+                GROUP BY lime_labels.lid
+                HAVING COUNT(DISTINCT(lime_labels.code)) < COUNT(lime_labels.id)"
+            )->queryAll();
+            foreach ($lids as $lid) {
+                regenerateLabelCodes400($lid['lid']);
             }
-            $oDB->createCommand()->update('{{settings_global}}', array('stg_value' => 474), "stg_name='DBVersion'");
+            $oDB->createCommand()->createIndex('{{idx5_labels}}', '{{labels}}', ['lid','code'], true);
+            $oDB->createCommand()->update('{{settings_global}}', array('stg_value' => 475), "stg_name='DBVersion'");
             $oTransaction->commit();
         }
     } catch (Exception $e) {
@@ -8075,3 +8035,46 @@ function runAddPrimaryKeyonAnswersTable400(&$oDB)
         $oDB->createCommand()->dropTable('answertemp');
     }
 }
+
+/**
+ * Regenerate codes for problematic label sets
+ * Helper function (TODO: Put in separate class)
+ * Fails silently
+ *
+ * @param int $lid Label set id
+ * @return void
+ */
+function regenerateLabelCodes400(int $lid)
+{
+    $oDB = Yii::app()->getDb();
+
+    $labelSet = $oDB->createCommand(
+        sprintf("SELECT * FROM {{labelsets}} WHERE lid = %d", (int) $lid)
+    )->queryRow();
+    if (empty($labelSet)) {
+        return;
+    }
+
+    foreach (explode(',', $labelSet['languages']) as $lang) {
+        $labels = $oDB->createCommand(
+            sprintf(
+                "SELECT * FROM {{labels}} WHERE lid = %d AND language = %s",
+                (int) $lid,
+                $oDB->quoteValue($lang)
+            )
+        )->queryAll();
+        if (empty($labels)) {
+            continue;
+        }
+        foreach ($labels as $key => $label) {
+            $oDB->createCommand(
+                sprintf(
+                    "UPDATE {{labels}} SET code = %s WHERE id = %d",
+                    // Use simply nr as label code
+                    $oDB->quoteValue((string) $key + 1),
+                    $label['id']
+                )
+            )->execute();
+        }
+    }
+}
diff --git a/installer/create-database.php b/installer/create-database.php
index ccfb4bf18a9..6daaf44aae4 100755
--- a/installer/create-database.php
+++ b/installer/create-database.php
@@ -175,6 +175,7 @@ function populateDatabase($oDB)
         $oDB->createCommand()->createIndex('{{idx1_labels}}', '{{labels}}', 'code', false);
         $oDB->createCommand()->createIndex('{{idx2_labels}}', '{{labels}}', 'sortorder', false);
         $oDB->createCommand()->createIndex('{{idx4_labels}}', '{{labels}}', ['lid','sortorder'], false);
+        $oDB->createCommand()->createIndex('{{idx5_labels}}', '{{labels}}', ['lid','code'], true);
 
         // label_l10ns
         $oDB->createCommand()->createTable('{{label_l10ns}}', array(