Rails - Nov 2004 - ActiveRecord and data integrity

Okay, this is a really basic question from a newbie to ActiveRecord.  
I''ve written nothing more than a small sample script testing it out.  
But I''m wondering a little bit about data integrity and race 
conditions.  My question is:  Is there anything in ActiveRecord that 
selects data and then runs inserts or updates based on information 
retrieved during select?  If so, does it put the full sequence of 
operations inside of a transaction?  What about for databases like MySQL 
with MyISAM tables, where transactions aren''t possible?  With good 
design and an occasional LOCK TABLES, data integrity can be ensured, but 
I''m concerned that maybe ActiveRecord isn''t doing this.

Thanks,
Carl Youngblood

> Is there anything in ActiveRecord that selects data and then runs 
> inserts or updates based on information retrieved during select?
Nothing that isn''t run within a transaction (if you should find 
otherwise, it''s a bug to report). If you run MyISAM, you''ve
chosen not
to care about such things and will have to do LOCK TABLE and friends 
manually.
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