I run MySqlin ubuntu 10.10. I created a table called 'employee'three empno field names , name and salary . Insert multiple objects. In the middle of the process, I want to change the salary attribute as 'NOT NULL'. i change the table as
ALTER TABLE employee MODIFY salary int(10) NOT NULL;
The request is in progress. I wanted to test with the command
UPDATE employee SET salary=NULL;
Query OK, 15 rows affected, 15 warnings (0.06 sec)
Rows matched: 15 Changed: 15 Warnings: 15
also issued warnings " (Code 1048): Column 'salary' cannot be null "(repeated for each line)
But when I saw my table, all salaries were zeros ( '0').
The same queries result in an error instead of a warning in WINDOWS XP MySql
I tested both the INNODB and MYISAM engines, but the same result. Please help me find out what happened next to the processing.
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