Readable Code for Modify_Snapshot_Settings

It annoyed me slightly that when I googled modify_snapshot_settings just now and all of the examples used huge numbers for the retention with (at best) a brief comment saying what the number meant. Here is a better example with slightly more readable code. Hope a few people down the road cut-and-paste from this article instead and the world gets a few more lines of readable code as a result. :)

On a side note, let me re-iterate the importance of increasing the AWR retention defaults. There are a few opinions about the perfect settings but everyone agrees that the defaults are a “lowest common denominator” suitable for demos on laptops but never for production servers. The values below are what I’m currently using.

    retention => 105 * 24 * 60,   -- days * hr/day * min/hr  (result is in minutes)
    interval  => 15);             -- minutes

SQL> select * from dba_hist_wr_control;
Pivoting output using Tom Kyte's printtab....
DBID                          : 3943732569
SNAP_INTERVAL                 : +00000 00:15:00.0
RETENTION                     : +00105 00:00:00.0
TOPNSQL                       : DEFAULT

PL/SQL procedure successfully completed.

Elapsed: 00:00:00.10

About Jeremy

Building and running reliable data platforms that scale and perform. about.me/jeremy_schneider


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This is my personal website. The views expressed here are mine alone and may not reflect the views of my employer.

contact: 312-725-9249 or schneider @ ardentperf.com




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