You can find out whether access plans for a query workload
would be improved by a set of indexes that you tested virtually.
About this task
In this procedure, you generate an EXPLAIN snapshot just
before running the Workload Index Advisor. You then run a virtual
test of a set of indexes, which are called candidate indexes because
they are candidates for being created, altered, or dropped. When you
run the test, a virtual EXPLAIN snapshot is generated. This virtual
snapshot makes use of the results of the test. Finally, you compare
this virtual snapshot with the EXPLAIN snapshot that you generated
when you ran the Workload Index Advisor.
To compare access plans from before testing candidate
indexes and from after testing candidate indexes:
What to do next
On the
Comparison History page,
double-click the entry for the comparison. On the
View Comparison
Results by Workload EXPLAIN Snapshots and SQL Statements page,
review the
Statements table to look for statements
with differences in the two EXPLAIN snapshots. If you need to share
the results with other people, select
Generate Comparison
HTML Report in the
More actions field
above the table.