Database Reference
In-Depth Information
depicts an excerpt of an AWR SQL report in HTML format with two execution plans for a single
SQL_ID
.
Figure 26-1.
AWR SQL report with multiple plans for a single statement
Lessons Learned
Retrieving execution plans for SQL statements captured with SQL trace from AWR is useful for
retrieving plans absent from SQL trace files or for comparisons of current and past execution
plans. Execution plans may change over time for various reasons such as these:
Changes in optimizer parameters
Updated optimizer statistics (
DBMS_STATS
or
ANALYZE
)
Software upgrades or downgrades
Partitioning of tables or indexes, which were previously not partitioned
Bind variable peeking
