|
SQL>
SQL> create table employees(
2 empno NUMBER(4)
3 , ename VARCHAR2(8)
4 , init VARCHAR2(5)
5 , job VARCHAR2(8)
6 , mgr NUMBER(4)
7 , bdate DATE
8 , msal NUMBER(6,2)
9 , comm NUMBER(6,2)
10 , deptno NUMBER(2) ) ;
Table created.
SQL>
SQL>
SQL> insert into employees values(1,'Jason', 'N', 'TRAINER', 2, date '1965-12-18', 800 , NULL, 10);
1 row created.
SQL> insert into employees values(2,'Jerry', 'J', 'SALESREP',3, date '1966-11-19', 1600, 300, 10);
1 row created.
SQL> insert into employees values(3,'Jord', 'T' , 'SALESREP',4, date '1967-10-21', 1700, 500, 20);
1 row created.
SQL> insert into employees values(4,'Mary', 'J', 'MANAGER', 5, date '1968-09-22', 1800, NULL, 20);
1 row created.
SQL> insert into employees values(5,'Joe', 'P', 'SALESREP',6, date '1969-08-23', 1900, 1400, 30);
1 row created.
SQL> insert into employees values(6,'Black', 'R', 'MANAGER', 7, date '1970-07-24', 2000, NULL, 30);
1 row created.
SQL> insert into employees values(7,'Red', 'A', 'MANAGER', 8, date '1971-06-25', 2100, NULL, 40);
1 row created.
SQL> insert into employees values(8,'White', 'S', 'TRAINER', 9, date '1972-05-26', 2200, NULL, 40);
1 row created.
SQL> insert into employees values(9,'Yellow', 'C', 'DIRECTOR',10, date '1973-04-27', 2300, NULL, 20);
1 row created.
SQL> insert into employees values(10,'Pink', 'J', 'SALESREP',null,date '1974-03-28', 2400, 0, 30);
1 row created.
SQL>
SQL> create MATERIALIZED VIEW dept20_mv as
2 select * from employees where deptno = 20;
select * from employees where deptno = 20
*
ERROR at line 2:
ORA-12014: table 'EMPLOYEES' does not contain a primary key constraint
SQL>
SQL> alter MATERIALIZED VIEW dept20_mv enable query rewrite;
alter MATERIALIZED VIEW dept20_mv enable query rewrite
*
ERROR at line 1:
ORA-12003: materialized view "JAVA2S"."DEPT20_MV" does not exist
SQL>
SQL> set autotrace on explain
SQL>
SQL> select *
2 from employees
3 where deptno = 20
4 and job = 'TRAINER';
no rows selected
Execution Plan
----------------------------------------------------------
Plan hash value: 1445457117
-------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
-------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | 90 | 2 (0)| 00:00:01 |
|* 1 | TABLE ACCESS FULL| EMPLOYEES | 1 | 90 | 2 (0)| 00:00:01 |
-------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
1 - filter("DEPTNO"=20 AND "JOB"='TRAINER')
Note
-----
- dynamic sampling used for this statement
SQL>
SQL> explain plan for
2 select * from employees
3 where deptno = 20 and job = 'TRAINER';
Explained.
SQL>
SQL> select * from table(dbms_xplan.display);
PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
Plan hash value: 1445457117
-------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
-------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | 90 | 2 (0)| 00:00:01 |
|* 1 | TABLE ACCESS FULL| EMPLOYEES | 1 | 90 | 2 (0)| 00:00:01 |
-------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
1 - filter("DEPTNO"=20 AND "JOB"='TRAINER')
Note
-----
- dynamic sampling used for this statement
17 rows selected.
Execution Plan
----------------------------------------------------------
Plan hash value: 2137789089
--------------------------------------------------------------------------------
-------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU
)| Time |
--------------------------------------------------------------------------------
-------------
| 0 | SELECT STATEMENT | | 8168 | 16336 | 29 (0
)| 00:00:01 |
| 1 | COLLECTION ITERATOR PICKLER FETCH| DISPLAY | | |
| |
--------------------------------------------------------------------------------
-------------
SQL>
SQL> set autotrace off
SQL>
SQL> drop table employees;
Table dropped.
SQL>
SQL>
|