Levels of detail
To control the amount of data, which can be very large especially for Explain plan or package, you can request summary and detail level Explain reports.
- A summary report shows one line for each SQL statement.
A summary block is always printed at the end of a report.
- This produces a full report for each SQL statement, which shows:
- “Raw” SQL EXPLAIN data as found in the PLAN_TABLE
- Access path data
- Table and table space data
- Index data, this shows:
- All available indexes for a given table
- Indexes selected for the access only
- Key data
- Plan and package data
- Host variables data
- Summary page
The number of data blocks listed varies with the Explain function requested.
- This shows raw data from the PLAN_TABLE and Access Path Data blocks in the report for each SQL statement. Information from the catalog tables is not included.
- The Access Path Data block is shown for each SQL statement.
- Index Data
- All data blocks of the DETAIL level are shown except for the Key Data block.
- No Raw PLAN_TABLE Data
- All data blocks of the DETAIL level, except the raw PLAN_TABLE, are shown.
- Key Distribution
- All data blocks of the DETAIL level are shown including the distribution of the ten mostly used key values.