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CREATING EXPLAIN PLAN FOR ORACLE SQL


CREATING EXPLAIN PLAN FOR ORACLE SQL


The EXPLAIN PLAN statement displays execution plans chosen
by the Oracle optimizer for SELECT, UPDATE, INSERT, and
DELETE statements.

Run This Script  To create Plan Table

$ORACLE_HOME/rdbms/admin/utlxplan.sql

Execute the SQL command like the following.

SQL> explain plan for select * from ultimus.cor_trans_gl_hist where year=2009 order by

branch_id;

Explained

SQL> select * from table(dbms_xplan.display);

PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
Plan hash value: 1485638787
--------------------------------------------------------------------------------
| Id  | Operation          | Name              | Rows  | Bytes |TempSpc| Cost (%
--------------------------------------------------------------------------------
|   0 | SELECT STATEMENT   |                   |  2429K|   651M|       |   365K
|   1 |  SORT ORDER BY     |                   |  2429K|   651M|  1807M|   365K
|*  2 |   TABLE ACCESS FULL| COR_TRANS_GL_HIST |  2429K|   651M|       |   218K
--------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
   2 - filter(TO_NUMBER("YEAR")=2009)

14 rows selected

----------------------------------------------------------------------------------------------
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