Martín Alaimo

I’m currently working on a demo/tutorial on Evolutionary Database Development techniques and tools.

Since yesterday we installed a mysql in a client for some software configuration management operations, I decided to use mysql for the tutorial / demo at hand.

I found something strange when trying to add an auto-incremental column to an existing table.

Given this table:

 create table program (
required_solo_hs int not null,
required_inst_hs int not null,
int not null required_hs
) 

I tried to add a column id:

 alter table add column program id int not null auto_increment 

Getting the following error;

Script line: 1 Incorrect table definition;
There Can be only one auto column and it must be defined as a key

The solution is simply to indicate that the auto increment column is also primary key:

 alter table add column program id int not null auto_increment key, 

Again .. someone might find it useful.

Today -at Kleer- we went through the experience of installing MySQL 5.1 for the first time in Vista 64bits. Far from being a pleasant installation, as we’re used to, this made us sweat bullets sweat.

After downloading the 64bit installer, install and configure, the setup wizard wouldn’t stop giving the error:

ERROR 1045 (28000): Access denied for user 'root' @ 'localhost'

We tried many solutions but none worked. Except for the following:

1. Stop the service “MySQL” from “Control Panel-> Administrative Tools-> Services”

2. Go to “C:\Windows\System32″

3. Find the file cmd.exe, right click with SHIFT down and select “Run as administrator”

4. Run the following command:

mysqld - skip-grant-tables

5. Leave that window running

6. Open another terminal window, this time NOT as administrator: “Start-> Run-> cmd” ENTER

7. Run the following command:

mysql-u root mysql

8. Wala! We are inside. Run the following statement, changing a password mypass real you want setear:

UPDATE user SET Password = PASSWORD ('mypass') WHERE USER = 'root';
FLUSH PRIVILEGES;

9. Exit:

exit

10. Close the window

11. Close the window that was running as administrator

12. Open task manager and kill all processes named “mysqld” (there should be one, of another user “Administrator”)

13. Start the service from “Control Panel-> Administrative Tools-> Services”

14. Log in again, this time as we are used to:

mysql-u root-p

With this last step, you should be connected without problems. I hope this solution can serve someone and save some time.