Sage-Tips

How do I change the execution plan in Oracle?

Perform the following steps:

1. Open Enterprise Manager DB Control and login as the system user.
2. Select the Server tab.
3. Under Query Optimizer, select SQL Plan Control.
4. Select the SQL Plan Baseline tab.
5. Under Settings, select the link FALSE for Capture SQL Plan Baselines.

How do you create an execution plan for a query?

How to generate Execution Plans?

1. Once the query is written completely, you can hit “Ctrl + L” and it will generate the estimated execution plan.
2. You can also right-click on the query window and select “Display Estimated Execution Plan” from the context menu that appears.

Where can I find Explain Plan in Oracle query?

Running EXPLAIN PLAN EXPLAIN PLAN FOR SELECT last_name FROM employees; This explains the plan into the PLAN_TABLE table. You can then select the execution plan from PLAN_TABLE . This is useful if you do not have any other plans in PLAN_TABLE , or if you only want to look at the last statement.

How do I know if execution plan has changed?

You can check if the SQL execution plan has changed by using the Active Workload Repository (AWR). First, you need to find the SQL_ID for the relevant query. The view GV$SQL contains the most recent SQL. If you can’t find the query in this view, try DBA_HIST_SQLTEXT instead.

How do I change the execution plan in SQL Server?

5 Ways to Change Execution Plans Without Tuning

1. Change your SQL Server version.
2. Set your database compatibility level.
3. Set the database-scoped options.
4. Use a server-level trace flag like 4199, which at first sounds really simple, but buckle up.
5. Use a trace flag at the query level.

How do I delete an execution plan in Oracle?

Flush Bad SQL Plan from Shared Pool

1. 1) FIND ADDRESS AND HASH_VALUE OF SQL_ID SQL> select ADDRESS, HASH_VALUE from V$SQLAREA where SQL_ID like ‘7yc\%’; ADDRESS HASH_VALUE —————- ———- 000000085FD77CF0 808321886.
2. 2) PURGE THE PLAN FROM SHARED POOL.

How do I get a plan handle query plan?

To retrieve a snapshot of all query plans residing in the plan cache, retrieve the plan handles of all query plans in the cache by querying the sys. dm_exec_cached_plans dynamic management view. The plan handles are stored in the plan_handle column of sys. dm_exec_cached_plans .

How do you use explain plan?

To explain a SQL statement, use the EXPLAIN PLAN FOR clause immediately before the statement. For example: EXPLAIN PLAN FOR SELECT last_name FROM employees; This explains the plan into the PLAN_TABLE table.

How do I find the hash value in a query plan?

Query to find Plan Hash Values for a SQLID in Oracle

1. SELECT DISTINCT sql_id, plan_hash_value.
2. FROM dba_hist_sqlstat dhs,
3. (
4. SELECT /*+ NO_MERGE */ MIN(snap_id) min_snap, MAX(snap_id) max_snap.
5. FROM dba_hist_snapshot ss.
6. WHERE ss.begin_interval_time BETWEEN (SYSDATE – &No_Days) AND SYSDATE.
7. ) s.

How do you get explain plan for a Sql_id in Oracle?

How to generate explain plan in oracle

1. Explain plan for a sql_id from cursor. set lines 2000 set pagesize 2000 SELECT * FROM table(DBMS_XPLAN.
2. Explain plan of a sql_id from AWR: SELECT * FROM table(DBMS_XPLAN.
3. Explain plan of sql baseline:
4. Explain plan for sql id from sql tuning set:

How do I change query execution plan?

How do I get the execution plan of a query in SQL Server?

To display the estimated execution plan for a query

1. On the toolbar, click Database Engine Query.
2. Enter the query for which you would like to display the estimated execution plan.
3. On the Query menu, click Display Estimated Execution Plan or click the Display Estimated Execution Plan toolbar button.