Re: What's the " latch "

Trister,

Latches are kind of like locks. Locks will "lock" data in a table so that only one user can update the data at a time. Latches also lock things, but instead of tables or rows in a table being locked, latches lock memory structures or other things that Oracle needs to get it's job done. Simply put, locks lock the data from simultaneous update by more than one user and latches lock the Oracle internal structures to prevent simultaneous access to the structures by more than one user.

HTH,
Brian

Trister Yang wrote:
>
> I have read in oracle concept, but I really don't know what's the
> "latch" mean?
>
> I will appreciate for any reply!
 

-- 
========================================
Brian Peasland
Raytheons Systems at
  USGS EROS Data Center
These opinions are my own and do not
necessarily reflect the opinions of my 
company!
========================================