From: Ken Bloom <kbloom@...>
Date: 2007-08-20T02:09:58+09:00
Subject: Re: Getting MySQL column comment metadata?

On Sun, 19 Aug 2007 23:33:35 +0900, Mario T. Lanza wrote:

> Hi All,
> 
> How do I go about getting the "Comments" metadata--the one I type via
> MySQL Administrator, for example--associated with a MySQL column?
> 
> I have been able to pull metadata from both ActiveRecord and DBI but
> cannot seem to find this added bit of info.

This doesn't appear to be implemented directily in MySQL's C API. 
Certainly it's not implemented in the direct MySQL Ruby API (see http://
www.tmtm.org/en/mysql/ruby/ and have a look at fetch_fields and the 
Mysql::Field class). Since DBD::Myql uses fetch_fields to determine what 
metadata is available, it's not available in dbi. I don't know about 
ActiveRecord, but I would expect the same thing.

The only way I know of to get this information is by running a "show full 
columns from TABLENAME" or using INFORMATION_SCHEMA. (Well, there's "show 
create table" too, but that requires parsing -- why use that when you 
have "show full columns")

--Ken

-- 
Ken Bloom. PhD candidate. Linguistic Cognition Laboratory.
Department of Computer Science. Illinois Institute of Technology.
http://www.iit.edu/~kbloom1/