When you edit the SQL query string directly you should pay attention to the indicators. For example s:6:"onecol" denotes a string of 6 characters. When you replace onecol with twocol this will work because both are 6 characters long, but if you replace it with threecol without also altering the number, the value saved to the database is threeco because it truncates it to 6 characters. Most servers have some degree of syntax correction but it’s a good idea to pay attention to it.