From: "NARUSE, Yui" <naruse@...>
Date: 2009-07-12T22:32:35+09:00
Subject: [ruby-core:24294] Re: [ANN] meeting log of RubyDeveloperKaigi20090622

Joel VanderWerf wrote:
> Is there a pure ruby sqlite library, or for that matter _any_ pure ruby 
> sql rdbms library? Google doesn't find anything in the first few pages 
> of hits (not counting pure ruby clients to sql dbs, and pure ruby sql 
> generators).

I thought this is fiction at present.

> If there were, would anyone use it? Seems doubtful, due to the 
> "performance be damned" comment. Supporting a significant fraction of 
> SQL and RDB seems like a huge effort for marginal value.

If truely damned, anyone doesn't use it.
This is matter of degree.

> Tell me again, why does out-of-the-box ruby need a sql database? For 
> most simple purposes (config files, saving program state) aren't yaml, 
> marshal, and pstore enough? For more complex purposes, there are gems, 
> and there is the unavoidable need to make choices. Sqlite isn't even 
> always the best choice for lightweight db (if you value thread/process 
> concurrency and don't care about sql, then IMO fsdb is a better choice).

In bundled libraries we have some persistent libraries:
dbm series and Marshal series.

DBM series are key-value store. So structured data are hard to store in.

Marshal series can be used by some ways.
If store objects as-is, data is weak at changing models.
If store objects as array-hash structure, selecting a certain object
will be hard work.
RDBMS seems better than them.

For very complex and huge purposes, using MySQL or some gems is right.
Recently however people use RDBMS to store settings.
Firefox and Google Gears may be good example.

-- 
NARUSE, Yui  <naruse@airemix.jp>