Hi,
I’m creating a simple Migration that adds test data to my database.
A Form has many Elements and every Element belongs to a Form. An element has the mandatory columns name, type and value.
“type” is a reserved field name for single table inheritance (STI): http://wiki.rubyonrails.com/rails/pages/MagicFieldNames
We’re using “timestamp” without a problem in some of our apps, so that must be another issue.
Commander Johnson wrote: ...snip...
Gives the error:
Mysql::Error: #23000Column 'type' cannot be null: INSERT INTO `elements` (`form_id`, `ordering`, `name`, `title`, `type`, `value`, `flags`, `created_at`, `updated_at`) VALUES(2, NULL, 'First Name', NULL, NULL, '', NULL, '2008-09-16 13:59:36', '2008-09-16 13:59:36')
As you can see, the 'type' column somehow isn't inserted.
From looking at that error it's clear that the 5th value sent is NULL which is your `type` column. So your problem is not with MySQL. Given that Rails uses a "type" column for single-table inheritance, maybe that has something to do with your issue.
I had similar issues when trying to add a column called 'timestamp'.
MySQL has a TIMESTAMP data type. I would guess that you could use that as a column name as long as it's quoted properly (i.e. `timestamp`).
I tend to avoid naming columns with likely database keywords (type, timestamp, data, time, number, text, etc.).
P.S. I also avoid using TIMESTAMP data type in MySQL. It's may not behave as you might expect it to. If a column of that type is not send in a UPDATE statement it will automatically update itself to the current time of the database server.