JPQL: set a column to null in an update

Question

The following JPQL:

UPDATE SignIn signIn SET signIn.cookieUUID = null WHERE signIn.user.id = :userID

Gives me the following error because of the "= null":

Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'IS NULL WHERE `B0`.`ID` = 9' at line 1
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)

But it works when I set the field to an empty string (= '').

So how do you set a column to null using JQPL?

Answer 1

I think its NULL (in caps) ::Reference JPQL and Eclipselink

 UPDATE SignIn signIn SET signIn.cookieUUID = NULL WHERE signIn.user.id = :userID

Or use param query as :

     String sQuery = "UPDATE SignIn signIn SET signIn.cookieUUID = :cookieUUID "+
                 "WHERE signIn.user.id = :userID";
     Query query= entityManager.createQuery(sQuery );
     query.setParameter("cookieUUID", null);
     query.setParameter("userID", userID);
     query.executeUpdate();