How to alter or change column with ALTER TABLE

[terenceyuen]

I would like to change the type of Null to NO ,what is the command for this?
I've tried this one, but no luck to get it work.
ALTER TABLE claims_summary ALTER COLUMN advance_call_details SET NOT NULL;

Thanks.
Terence
+----------------------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------------------+--------------+------+-----+---------+-------+
| client_id | int(11) | | | 0 | |
| client_code | varchar(30) | | PRI | | |
| club_id | int(11) | | | 0 | |
| club_code | varchar(30) | | PRI | | |
| yearclaim | int(10) | | PRI | 0 | |
| advance_call | double(16,4) | YES | | 0.0000 | |
| additional_call | double(16,4) | YES | | 0.0000 | |
| supplementary_call | double(16,4) | YES | | 0.0000 | |
| release_call | double(16,4) | YES | | 0.0000 | |
| advance_call_details | varchar(240) | YES | | | |
+----------------------+--------------+------+-----+---------+-------+

[tashy]

Try this ALTER TABLE table name ALTER COLUMN column name data type NOT NULL


By data type ,it could either be int,bit,etc

[pbmods]

When you change or alter a column, you are basically redefining it, so you have to provide a full definition of the column, not just the attributes you want to change (otherwise, how would MySQL know if you wanted to remove an attribute from a column?).

P.S., Please surround your mysql output with CODE tags to make it easier to read next time. Thanks.

[terenceyuen]

Thanks a lot
, I'v tried, but it return the following errors at the end. Is it possible to define the datetype : varchar(240) ?

mysql> ALTER TABLE claims_summary ALTER COLUMN advance_call_details varchar(240) NOT NULL;

ERROR 1064: You have an error in your SQL syntax near 'varchar(240) NOT NULL' at line 1

[pradeep kaltari]

Thanks a lot
, I'v tried, but it return the following errors at the end. Is it possible to define the datetype : varchar(240) ?

mysql> ALTER TABLE claims_summary ALTER COLUMN advance_call_details varchar(240) NOT NULL;

ERROR 1064: You have an error in your SQL syntax near 'varchar(240) NOT NULL' at line 1

Hi,
Try this:

ALTER TABLE table_name MODIFY COLUMN column_name VARCHAR(240) NOT NULL
 

Regards,
Pradeep

[Atli]

Hi.

If you also want to change the name of the column you can do this:

ALTER TABLE myTable
CHANGE myCol 
  newName dataType NOT NULL;
 

[terenceyuen]

Thank you so much. It's very useful tips..