I’ve
often said that Oracle will have an easier time getting rid of the IO costing
model then Rule based optimizing. Rule
lives on in 12.1.0.1. Maybe in my life
time I’ll see the day when RULE is gone, but not this day.
C:\OP>sqlplus op/op
SQL*Plus: Release 12.1.0.1.0 Production on
Thu Dec 19 13:48:39 2013
Copyright (c) 1982, 2013, Oracle. All rights reserved.
Last Successful login time: Thu Dec 19 2013
13:44:55 -05:00
Connected to:
Oracle Database 12c Enterprise Edition
Release 12.1.0.1.0 - 64bit Production
With the Partitioning, OLAP, Advanced
Analytics and Real Application Testing options
SQL> alter session set OPTIMIZER_MODE =
rule;
SQL> @hxplan
Enter .sql file name (without extension): emp
Enter the display level (TYPICAL, ALL, BASIC,
SERIAL) [TYPICAL] :
Plan hash value: 1445457117
---------------------------------------
| Id |
Operation | Name |
---------------------------------------
| 0 |
SELECT STATEMENT | |
|* 1
| TABLE ACCESS FULL| EMPLOYEES |
---------------------------------------
Predicate Information (identified by
operation id):
---------------------------------------------------
1 -
filter("FIRST_NAME"='David')
Note
-----
-
rule based optimizer used (consider using cbo)
SQL>
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