Script to compare plan performance

Here’s a zip of a script I modified today: zip

Here’s an example output:

 QUERY_NUM SQL_ID        PLAN_HASH_VALUE EXECUTIONS AVG_ELAPSED OPTIMIZER_COST AVG_FETCHES  AVG_SORTS AVG_DISK_READS AVG_BUFFER_GETS   AVG_ROWS    AVG_CPU AVG_IOWAIT AVG_DIRECT_WRITES AVG_PHYS_READS AVG_PHYS_WRITES
---------- ------------- --------------- ---------- ----------- -------------- ----------- ---------- -------------- --------------- ---------- ---------- ---------- ----------------- -------------- ---------------
         1 gxk0cj3qxug85      2051250004   39504258  31630.2852             15  4.71993394 .444248288     4.07294381      440.124393 41.3960784 3447.83137 28056.5262                 0     .006406626               0
         1 gxk0cj3qxug85       548353012   24360619  31854.5456             15  4.73696596 .574941507     4.16225047      443.290799 41.5668639 3501.62695 28205.9349                 0     .009019804               0
         2 53b6j9nvd2vwa       376144290    1069593  438746.758     19.6425025  33.7741683          0     58.9193684       3864.5447  332.18592 32952.0388 406548.271                 0     19.2981312               0
         2 53b6j9nvd2vwa       655563694    1008553  414586.506     15.0111675  33.7122908          0     58.6486828      3851.28671 331.575216 32283.0233 382834.453                 0     12.4507269               0
         2 53b6j9nvd2vwa      2504177057     274652  418157.478     19.5541562  32.8918486          0     61.1868838      3726.22908 323.358235 31005.0901 388545.269                 0     23.2050923               0
         3 4usguw7d6kxy4      2543632952    1070303   151648.49     12911.7175  2.30832577 .999997197     5.49557555      6221.80141 16.7674061 130072.596 10153.4778                 0     .388805787               0
         3 4usguw7d6kxy4      3221641997     996033  151860.479      11987.696  2.22684489 .999998996     7.10842914      6073.16306  15.902446  127194.45 13655.9405                 0     .316254582               0
         3 4usguw7d6kxy4      1764817920          2    277287.5          12860           1          1              1            6956          5     260000    10575.5                 0              1               0
         4 buhvbrfw1uyrd      2225737849    2871021  37985.4363     7.37064414  32.5216263          0      5.0695129      439.697767 319.641241 3463.90361 34645.8396                 0     2.01971389               0
         5 bvttgft3kj2hg      3569562598     293543  252814.965     20.6213018  95.7064212 .999996593     12.3908524      11035.1541 951.571562 137023.945 95634.8559                 0     1.94147365               0
         6 084v1t4whvzwd       883418687      70258  940211.781     4875.03099  1.00001423          0     30.6947394      22558.3683 .954980216 880713.798 16997.2457                 0     2.93185118               0
         7 972sx2uhfswn5       632842214  229406586  279.732773             14  1.00002261 .092121309     .003579313      25.6327361 .941600155 229.417607  23.334532                 0     .000786085               0

I’m using this script to help figure out which plans to lock in with SQL profiles.  For example, sql_id gxk0cj3qxug85 executes plan 2051250004 more often than plan 548353012 and they seem similar in performance so maybe it would be safe to just lock in the first plan.

I’ve also been reviewing the plans manually to see if there were major differences or if the plans were essentially the same.

I had a few minutes so I thought I would pass this along.

– Bobby

About Bobby

I live in Chandler, Arizona with my wife and three daughters. I work for US Foods, the second largest food distribution company in the United States. I've been working as an Oracle database administrator and PeopleSoft administrator since 1994. I'm very interested in Oracle performance tuning.
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