MySql, InnoDB & Null Values

Posted by pws5068 on Stack Overflow See other posts from Stack Overflow or by pws5068
Published on 2010-06-06T00:19:22Z Indexed on 2010/06/06 0:22 UTC
Read the original article Hit count: 579

Filed under:

mysql

|

database

|

innodb

|

myisam

|

storage-engines

Formerly I was using MyISAM storage engine for MySql and I had defined the combination of three fields to be unique.

Now I have switched to InnoDB, which I assume caused this problem, and now NULL != NULL.

So for the following table:

ID (Auto) |  Field_A   | Field_B  | Field_C

I can insert (Field_A,Field_B,Field_C) Values(1,2,NULL) (1,2,NULL) (1,2,NULL) infinitely many times.

How can I prevent this behavior?

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