-ALTER TABLE /*_*/revision MODIFY rev_comment varbinary(767) NOT NULL;
-ALTER TABLE /*_*/archive MODIFY ar_comment varbinary(767) NOT NULL;
-ALTER TABLE /*_*/image MODIFY img_description varbinary(767) NOT NULL;
-ALTER TABLE /*_*/oldimage MODIFY oi_description varbinary(767) NOT NULL;
-ALTER TABLE /*_*/filearchive MODIFY fa_description varbinary(767);
+ALTER TABLE /*_*/revision MODIFY rev_comment varbinary(767) NOT NULL default '';
+ALTER TABLE /*_*/archive MODIFY ar_comment varbinary(767) NOT NULL default '';
+ALTER TABLE /*_*/image MODIFY img_description varbinary(767) NOT NULL default '';
+ALTER TABLE /*_*/oldimage MODIFY oi_description varbinary(767) NOT NULL default '';
+ALTER TABLE /*_*/filearchive MODIFY fa_description varbinary(767) default '';