diff --git a/js/src/modules/functions.js b/js/src/modules/functions.js
index 833e35c72f..72950db7ee 100644
--- a/js/src/modules/functions.js
+++ b/js/src/modules/functions.js
@@ -56,36 +56,6 @@ let sqlAutoCompleteDefaultTable = '';
  */
 window.centralColumnList = [];
 
-/**
- * Array to hold 'Primary' index columns.
- * @type {array}
- */
-window.primaryIndexes = [];
-
-/**
- * Array to hold 'Unique' index columns.
- * @type {array}
- */
-window.uniqueIndexes = [];
-
-/**
- * Array to hold 'Index' columns.
- * @type {array}
- */
-window.indexes = [];
-
-/**
- * Array to hold 'Fulltext' columns.
- * @type {array}
- */
-window.fulltextIndexes = [];
-
-/**
- * Array to hold 'Spatial' columns.
- * @type {array}
- */
-window.spatialIndexes = [];
-
 /**
  * Make sure that ajax requests will not be cached by appending a random variable to their parameters.
  * @return {function}
diff --git a/js/src/modules/indexes.js b/js/src/modules/indexes.js
index 14becaf751..64a32c1f06 100644
--- a/js/src/modules/indexes.js
+++ b/js/src/modules/indexes.js
@@ -14,6 +14,47 @@ import { ajaxRemoveMessage, ajaxShowMessage } from './ajax-message.js';
  */
 const Indexes = {};
 
+/**
+ * Array to hold 'Primary' index columns.
+ * @type {array}
+ */
+let primaryColumns = [];
+
+/**
+ * Array to hold 'Unique' index columns.
+ * @type {array}
+ */
+let uniqueColumns = [];
+
+/**
+ * Array to hold 'Index' columns.
+ * @type {array}
+ */
+let indexColumns = [];
+
+/**
+ * Array to hold 'Fulltext' columns.
+ * @type {array}
+ */
+let fulltextColumns = [];
+
+/**
+ * Array to hold 'Spatial' columns.
+ * @type {array}
+ */
+let spatialColumns = [];
+
+/**
+ * @return {void}
+ */
+Indexes.resetColumnLists = () => {
+    primaryColumns = [];
+    uniqueColumns = [];
+    indexColumns = [];
+    fulltextColumns = [];
+    spatialColumns = [];
+};
+
 /**
  * Returns the array of indexes based on the index choice
  *
@@ -22,23 +63,23 @@ const Indexes = {};
  * @return {null|object}
  */
 Indexes.getIndexArray = function (indexChoice) {
-    var sourceArray = null;
+    let sourceArray = null;
 
     switch (indexChoice.toLowerCase()) {
     case 'primary':
-        sourceArray = window.primaryIndexes;
+        sourceArray = primaryColumns;
         break;
     case 'unique':
-        sourceArray = window.uniqueIndexes;
+        sourceArray = uniqueColumns;
         break;
     case 'index':
-        sourceArray = window.indexes;
+        sourceArray = indexColumns;
         break;
     case 'fulltext':
-        sourceArray = window.fulltextIndexes;
+        sourceArray = fulltextColumns;
         break;
     case 'spatial':
-        sourceArray = window.spatialIndexes;
+        sourceArray = spatialColumns;
         break;
     default:
         return null;
@@ -570,12 +611,7 @@ Indexes.off = () => function () {
  * @return {function}
  */
 Indexes.on = () => function () {
-    // Re-initialize variables.
-    window.primaryIndexes = [];
-    window.uniqueIndexes = [];
-    window.indexes = [];
-    window.fulltextIndexes = [];
-    window.spatialIndexes = [];
+    Indexes.resetColumnLists();
 
     // for table creation form
     var $engineSelector = $('.create_table_form select[name=tbl_storage_engine]');
diff --git a/js/src/table/structure.js b/js/src/table/structure.js
index 1ba9c57766..897528a8d4 100644
--- a/js/src/table/structure.js
+++ b/js/src/table/structure.js
@@ -5,6 +5,7 @@ import { Navigation } from '../modules/navigation.js';
 import { CommonActions, CommonParams } from '../modules/common.js';
 import highlightSql from '../modules/sql-highlight.js';
 import { ajaxRemoveMessage, ajaxShowMessage } from '../modules/ajax-message.js';
+import { Indexes } from '../modules/indexes.js';
 
 /**
  * @fileoverview    functions used on the table structure page
@@ -58,11 +59,7 @@ AJAX.registerTeardown('table/structure.js', function () {
 });
 
 AJAX.registerOnload('table/structure.js', function () {
-    // Re-initialize variables.
-    window.primaryIndexes = [];
-    window.indexes = [];
-    window.fulltextIndexes = [];
-    window.spatialIndexes = [];
+    Indexes.resetColumnLists();
 
     /**
      *Ajax action for submitting the "Column Change" and "Add Column" form