From: Bob Hutchison <hutch@...>
Date: 2006-08-09T22:30:19+09:00
Subject: Looking for a Fast Persistent Store

Hi,

I'm looking for a persistent store, where:
  * I can use it from Ruby
  * it is fast
  * it is transactional
  * it can update more than one store in a single transaction
  * simple String -> String mappings in the store are sufficient
  * ideally uses files in the filesystem

These kinds of stores are normally implemented as persistent hashes  
or BTrees (or both). I know that Sleepycat's Berkeley DB <http:// 
www.sleepycat.com/> does this, and I've used Java based systems that  
do this. I also know of some C based things but they don't have Ruby  
wrappers. I can't find anything in the Ruby world, and I don't care  
too much if it isn't pure Ruby.

I know about Purple <http://purple.rubyforge.org/> and the QDMB Ruby  
wrapper <http://qdbm.sourceforge.net/>. Neither do the multiple hash/ 
BTree in a transaction thing.

The trick appears to be with transactions.

I know this can be done easily enough in a Relational DB, but I know  
that, for example, JDBC/MySQL combination is significantly slower at  
what I need to do than Perst (a pure Java thing that's startlingly  
fast). I've taken a look at sqlite, which satisfies all requirements  
but I can't shake this feeling that things can be better.

Does anyone have any ideas?

Thanks,
Bob

----
Bob Hutchison                  -- blogs at <http://www.recursive.ca/ 
hutch/>
Recursive Design Inc.          -- <http://www.recursive.ca/>
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