I'm new to SQL and have a test table in a database. I realized that my previous title size allocation was too small, so I want to increase it from a VARCHAR(120) to VARCHAR(500) by running the following command:
ALTER TABLE test MODIFY title VARCHAR(500);
ALTER TABLE test MODIFY COLUMN title VARCHAR(500);
Since you are not getting a syntax error and you have only a small number of rows, the most likely reason is that there is another process that's holding a lock on this table. Please connect any other clients that you have open. This could be other instances of mysql work bench, a long running script, the django console and so many things.
Then try the query again. If that still doesn't work, try
SHOW OPEN TABLES