Which of my sql statements are using dynamic sampling?

From a reply I gave on an OTN forum thread, how to see all queries currently in memory which use dynamic sampling?

Dynamic sampling is an attribute in V$SQL_PLAN.OTHER_XML.

In 11gR1, it says “yes”.
In 11gR2, it gives the level.

Using EXTRACTVALUE which is deprecated in 11.2:

select p.sql_id,  extractvalue(h.column_value,'/info') lvl
from   v$sql_plan p
,      table(xmlsequence(extract(xmltype(p.other_xml),'/other_xml/info'))) h
where  p.other_xml is not null
and    extractvalue(h.column_value,'/info/@type') = 'dynamic_sampling';

Another approach using one of the prefered alternatives – XMLTABLE:

select p.sql_id, t.val
from   v$sql_plan p
,      xmltable('for $i in /other_xml/info
                 where $i/@type eq "dynamic_sampling"
                 return $i'
                passing xmltype(p.other_xml)
                columns attr varchar2(50) path '@type',
                        val  varchar2(50) path '/') t
where  p.other_xml is not null;

Warning: I tried a number of approaches with XMLTABLE and whilst they all worked in 11.2.0.3, in 11.1.0.7 they all ran into the error below. It might well just be a local issue but I did not investigate:

ORA-00600: internal error code, arguments: [qctVCO:csform], [0], [0], [0], [0], [112], [2], [224], [], [], [], [] 
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One Response to Which of my sql statements are using dynamic sampling?

  1. Pingback: SQL utils using XML | OraStory

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