Re: Open cursors parameter

From: Joel Garry <joelga_at_pebble.ml.org>
Date: 6 May 1998 15:13:59 -0700
Message-ID: <6iqnb7$qvu$1@pebble.ml.org>

In article <35509DD5.40DE_at_virgajesse.be>, Nordine Vandezande <nordine.vandezande_at_virgajesse.be> wrote:
>The init-file of the database at my company has a parameter called OPEN
>CURSORS which has a value of 650. (The DBA who configured the database
>has left the firm)
>I've read that the initial value of this parameter (by installation) was
>50.
>
>What can be the reason for this higher value?

Usually, at some point someone got an error and asked the DBA to raise it. In some cases, DBA's are superstitious about it.

Cursors are areas in memory for SQL statement execution, requesting information from Oracle memory caches. Some programs use more than others. I've seen manufacturing packages require open_cursors=2000 or more.

The open_cursors value is the maxiumum that a session can have, so there is no real penalty to setting it too high. Setting it too low may blow a program, especially programs that use implicit cursors a lot.

More memory will be used if CURSOR_SPACE_FOR_TIME is true, because it keeps stuff like cursors around longer (speeding up things because the stuff doesn't need to be recreated). So programs that recurse or don't clean up after themselves may be more touchy about open_cursors.

See your server concepts, reference and administrator guides.

>
>Thanks in advance.

--
These opinions are my own and not necessarily those of Information Quest

jgarry@eiq.com                           http://www.informationquest.com

http://ourworld.compuserve.com/homepages/joel_garry "See your DBA?" I AM the @#%*& DBA! Received on Wed May 06 1998 - 17:13:59 CDT