diff --git a/lib/db/mysql.sql b/lib/db/mysql.sql
index 0e86036fbd6..059b6d0163f 100644
--- a/lib/db/mysql.sql
+++ b/lib/db/mysql.sql
@@ -53,7 +53,7 @@ CREATE TABLE `prefix_course` (
   `summary` text NOT NULL,
   `format` varchar(10) NOT NULL default 'topics',
   `showgrades` smallint(2) unsigned NOT NULL default '1',
-  `modinfo` longtext NOT NULL,
+  `modinfo` longtext NOT NULL default '',
   `newsitems` smallint(5) unsigned NOT NULL default '1',
   `teacher` varchar(100) NOT NULL default 'Teacher',
   `teachers` varchar(100) NOT NULL default 'Teachers',
@@ -99,7 +99,7 @@ CREATE TABLE `prefix_course` (
 CREATE TABLE `prefix_course_categories` (
   `id` int(10) unsigned NOT NULL auto_increment,
   `name` varchar(255) NOT NULL default '',
-  `description` text NOT NULL,
+  `description` text NOT NULL default '',
   `parent` int(10) unsigned NOT NULL default '0',
   `sortorder` int(10) unsigned NOT NULL default '0',
   `coursecount` int(10) unsigned NOT NULL default '0',
@@ -223,7 +223,7 @@ CREATE TABLE `prefix_course_allowed_modules` (
 CREATE TABLE `prefix_event` (
   `id` int(10) unsigned NOT NULL auto_increment,
   `name` varchar(255) NOT NULL default '',
-  `description` text NOT NULL,
+  `description` text NOT NULL default '',
   `format` int(4) unsigned NOT NULL default '0',
   `courseid` int(10) unsigned NOT NULL default '0',
   `groupid` int(10) unsigned NOT NULL default '0',
@@ -370,7 +370,7 @@ CREATE TABLE `prefix_groups` (
   `id` int(10) unsigned NOT NULL auto_increment,
   `courseid` int(10) unsigned NOT NULL default '0',
   `name` varchar(254) NOT NULL default '',
-  `description` text NOT NULL,
+  `description` text NOT NULL default '',
   `password` varchar(50) NOT NULL default '',
   `lang` varchar(10) NOT NULL default 'en',
   `theme` varchar(50) NOT NULL default '',
@@ -516,7 +516,7 @@ CREATE TABLE `prefix_scale` (
   `userid` int(10) unsigned NOT NULL default '0',
   `name` varchar(255) NOT NULL default '',
   `scale` text NOT NULL,
-  `description` text NOT NULL,
+  `description` text NOT NULL default '',
   `timemodified` int(10) unsigned NOT NULL default '0',
   PRIMARY KEY  (id),
   KEY `courseid` (`courseid`)