[wp-hackers] Metadata Mess

[Mike Schinkel]

On Dec 22, 2009, at 3:42 PM, Malaiac wrote:
> 2009/12/22 Joseph Scott <joseph at josephscott.org>:
>> Please DON'T use ENUM.  Aside from the DB portability issues that
>> Peter brought up, ALTER TABLE in performance in MySQL can be pretty
>> bad.  MySQL does a full table copy for table ALTERations.  There are
>> very involved hacks to improve that process, but they aren't for the
>> average WP user.
>> 
>> Adding and removing object_type's should be easy, with minimal impact.
>>  Using ENUM is highly intrusive and high impact.
> 
> See, you are focused on portability and one time performance of an
> ALTER table. I'm focused on long term performance of heavily used meta
> tables. No way I'm gonna suffer a VARCHAR search for each and every
> meta. There are sites with more than 20 000 comments on a single page.
> There are sites with more than 30 meta values per post. ...

I'd agree withthe  long term vs. one time concern.  

-Mike Schinkel