Oracle_071_lesson_p15

Posted 2020-12-29

???????????????   rename   may   table   ted   modify   mail   x86   dep   

Managing Schema Objects??????????????????

you should be able to:
1???Manage constraints
2???Create and use temporary tables
3???Create and use external tables

Use the ALTER TABLE statement to:
1???Add or drop a constraint, but not to modify its structure
2???Enable or disable constraints
3???Add a NOT NULL constraint by using the MODIFY clause

ALTER TABLE <table_name>
ADD [CONSTRAINT <constraint_name>]
type (<column_name>);

ALTER TABLE emp2
MODIFY employee_id PRIMARY KEY;

ALTER TABLE emp2
ADD CONSTRAINT emp_mgr_fk
FOREIGN KEY(manager_id)
REFERENCES emp2(employee_id);

ALTER TABLE emp2
DROP CONSTRAINT emp_mgr_fk;

ALTER TABLE emp2
DROP PRIMARY KEY CASCADE; ????????????

ALTER TABLE myemp2
DROP CONSTRAINT emp_name_pk ONLINE;

ALTER TABLE dept2 ADD CONSTRAINT dept_lc_fk
FOREIGN KEY (location_id)
REFERENCES locations(location_id) ON DELETE CASCADE; ????????????????????????

ALTER TABLE emp2 ADD CONSTRAINT emp_dt_fk
FOREIGN KEY (Department_id)
REFERENCES departments(department_id) ON DELETE SET NULL; ????????????????????????

ALTER TABLE emp2
DROP COLUMN employee_id CASCADE CONSTRAINTS;

ALTER TABLE test1
DROP (col1_pk, col2_fk, col1);

ALTER TABLE marketing RENAME to new_marketing; ?????????

ALTER TABLE new_marketing RENAME COLUMN team_id TO id; ?????????

ALTER TABLE new_marketing RENAME CONSTRAINT mktg_pk TO new_mktg_pk; ????????????

ALTER TABLE emp2 DISABLE CONSTRAINTS emp_dt_pk;

ALTER TABLE dept2 DISABLE primary key CASCADE;

ALTER TABLE emp2 ENABLE CONSTRAINT emp_dt_fk;

A UNIQUE index is automatically created if you enable a UNIQUE key or a PRIMARY KEY constraint.
??????????????????????????????????????????????????????????????? ?????????????????????????????????

An integrity constraint defined on a table can be in one of the following states:
1???ENABLE?VALIDATE
2???ENABLE?NOVALIDATE
3???DISABLE?VALIDATE
4???DISABLE?NOVALIDATE

ALTER TABLE dept2
ENABLE NOVALIDATE PRIMARY KEY;

Constraints can have the following attributes:
DEFERRABLE ?????? or NOT DEFERRABLE ?????????
INITIALLY DEFERRED ??????????????? or INITIALLY IMMEDIATE ?????????????????????

ALTER TABLE dept2
ADD CONSTRAINT dept2_id_pk
PRIMARY KEY (department_id)
DEFERRABLE INITIALLY DEFERRED;

SET CONSTRAINTS dept2_id_pk IMMEDIATE;

ALTER SESSION SET CONSTRAINTS= IMMEDIATE;

CREATE TABLE emp_new_sal (salary NUMBER
CONSTRAINT sal_ck
CHECK (salary > 100)
DEFERRABLE INITIALLY IMMEDIATE,
bonus NUMBER
CONSTRAINT bonus_ck
CHECK (bonus > 0 )
DEFERRABLE INITIALLY DEFERRED );

DROP TABLE emp_new_sal PURGE; ????????????

Creating and using temporary tables ???????????????
When session/transaction completes
????????????????????? ??????commit???????????????????????????????????????????????????????????????
????????????????????? ??????commit??????????????????????????? ???????????????????????????
SQL> / ?????????????????????

CREATE GLOBAL TEMPORARY TABLE cart(n NUMBER,d DATE) ON COMMIT DELETE ROWS;

CREATE GLOBAL TEMPORARY TABLE today_sales
ON COMMIT PRESERVE ROWS AS
SELECT * FROM orders
WHERE order_date = SYSDATE;

Creating a Directory for the External Table ???????????????
??????????????????????????????

CREATE OR REPLACE DIRECTORY emp_dir
AS ???/???/emp_dir???;

GRANT READ ON DIRECTORY emp_dir TO ora_21;

CREATE TABLE <table_name> ( <col_name> <datatype>, ??? )
ORGANIZATION EXTERNAL
(TYPE <access_driver_type>
DEFAULT DIRECTORY <directory_name>
ACCESS PARAMETERS
(??? ) )
LOCATION (???<location_specifier>???) REJECT LIMIT [0 | <number> | UNLIMITED];

CREATE TABLE oldemp (fname char(25), lname CHAR(25))
ORGANIZATION EXTERNAL
(TYPE ORACLE_LOADER
DEFAULT DIRECTORY emp_dir
ACCESS PARAMETERS
(RECORDS DELIMITED BY NEWLINE
FIELDS(fname POSITION ( 1:20) CHAR,
lname POSITION (22:41) CHAR))
LOCATION (???emp.dat???));

SELECT * FROM oldemp;

CREATE TABLE emp_ext
(employee_id, first_name, last_name)
ORGANIZATION EXTERNAL
(
TYPE ORACLE_DATAPUMP #?????????
DEFAULT DIRECTORY emp_dir
LOCATION
(???emp1.exp???,???emp2.exp???)
)
PARALLEL
AS
SELECT employee_id, first_name, last_name
FROM employees;

??????????????????????????????????????????????????????????????????????????????????????????????????????????????????oracle_loader???oracle_datapump,oracle_loader????????????sqlldr???????????????????????????flat???????????????oracle_datapump??????datapump??????????????????????????????oracle_datapump???????????????dmp?????????

------oracle_loader
----??????????????????????????????????????????
====a.dat====
360,Jane,Janus,ST_CLERK,121,17-MAY-2001,3000,0,50,jjanus
361,Mark,Jasper,SA_REP,145,17-MAY-2001,8000,.1,80,mjasper
362,Brenda,Starr,AD_ASST,200,17-MAY-2001,5500,0,10,bstarr
363,Alex,Alda,AC_MGR,145,17-MAY-2001,9000,.15,80,aalda

====b.dat====
401,Jesse,Cromwell,HR_REP,203,17-MAY-2001,7000,0,40,jcromwel
402,Abby,Applegate,IT_PROG,103,17-MAY-2001,9000,.2,60,aapplega
403,Carol,Cousins,AD_VP,100,17-MAY-2001,27000,.3,90,ccousins
404,John,Richardson,AC_ACCOUNT,205,17-MAY-2001,5000,0,110,jrichard

----?????????????????????
CONNECT / AS SYSDBA;
-- Set up directories and grant access to hr
CREATE OR REPLACE DIRECTORY admin_dat_dir
AS ???/u01/backup???;
CREATE OR REPLACE DIRECTORY admin_log_dir
AS ???/u01/backup???;
CREATE OR REPLACE DIRECTORY admin_bad_dir
AS ???/u01/backup???;
GRANT READ ON DIRECTORY admin_dat_dir TO sun;
GRANT WRITE ON DIRECTORY admin_log_dir TO sun;
GRANT WRITE ON DIRECTORY admin_bad_dir TO sun;

----??????loader??????????????????????????????????????????????????????
conn sun/sun
-- create the external table
CREATE TABLE admin_ext_employees
(employee_id NUMBER(4),
first_name VARCHAR2(20),
last_name VARCHAR2(25),
job_id VARCHAR2(10),
manager_id NUMBER(4),
hire_date DATE,
salary NUMBER(8,2),
commission_pct NUMBER(2,2),
department_id NUMBER(4),
email VARCHAR2(25)
)
ORGANIZATION EXTERNAL
(
TYPE ORACLE_LOADER
DEFAULT DIRECTORY admin_dat_dir
ACCESS PARAMETERS
(
records delimited by newline
badfile admin_baddir:???empxt%a%p.bad???
logfile admin_logdir:???empxt%a%p.log???
fields terminated by ???,???
missing field values are null
( employee_id, first_name, last_name, job_id, manager_id,
hire_date char date_format date mask "dd-mon-yyyy",
salary, commission_pct, department_id, email
)
)
LOCATION (???a.dat???, ???b.dat???)
)
PARALLEL
REJECT LIMIT UNLIMITED;

create table emp as select * from admin_ext_employees;

SQL>
SQL> SELECT * FROM emp;

EMPLOYEE_ID FIRST_NAME LAST_NAME JOB_ID M

---

    401 Jesse                Cromwell                  HR_REP      
    402 Abby                 Applegate                 IT_PROG     
    403 Carol                Cousins                   AD_VP       
    404 John                 Richardson                AC_ACCOUNT  
    360 Jane                 Janus                     ST_CLERK    
    361 Mark                 Jasper                    SA_REP      
    362 Brenda               Starr                     AD_ASST     
    363 Alex                 Alda                      AC_MGR      

SQL> SELECT * FROM user_external_tables ;

no rows selected

[[email protected] backup]$ ls -l
total 20
-rw-r--r-- 1 ora11 oinstall 228 Sep 6 21:17 a.dat
-rw-r--r-- 1 ora11 oinstall 252 Sep 6 21:17 b.dat
-rw-r--r-- 1 ora11 oinstall 2826 Sep 6 21:19 empxt000_2756.log
-rw-r--r-- 1 ora11 oinstall 3110 Sep 6 21:19 empxt000_2763.log
-rw-r--r-- 1 ora11 oinstall 3110 Sep 6 21:19 empxt001_2765.log

------oracle_datapump
----?????????????????????????????????????????????datapump???????????????????????????????????????
----??????datapump????????????????????????????????????????????????????????????
SQL> CREATE TABLE admin_ext_employees
2 (employee_id ,
3 first_name ,
4 last_name ,
5 job_id ,
6 manager_id ,
7 hire_date ,
8 salary ,
9 commission_pct ,
10 department_id ,
11 email
12 )
13 ORGANIZATION EXTERNAL
14 (
15 TYPE ORACLE_DATAPUMP
16 DEFAULT DIRECTORY admin_dat_dir
17 LOCATION (???emp2.dmp???))
18 AS SELECT * FROM emp;

Table created.

----????????????????????????????????????XML???????????????
-rw-r----- 1 ora11 oinstall 12288 Sep 6 21:33 emp2.dmp
[[email protected] backup]$ strings emp2.dmp
"SUN"."U"
x86_64/Linux 2.4.xx

----??????loader??????????????????????????????????????????????????????
SQL> CREATE TABLE admin_ext_employees2
2 (employee_id NUMBER(4),
3 first_name VARCHAR2(20),
4 last_name VARCHAR2(25),
5 job_id VARCHAR2(10),
6 manager_id NUMBER(4),
7 hire_date DATE,
8 salary NUMBER(8,2),
9 commission_pct NUMBER(2,2),
10 department_id NUMBER(4),
11 email VARCHAR2(25)
12 )
13 ORGANIZATION EXTERNAL
14 (
15 TYPE ORACLE_DATAPUMP
16 DEFAULT DIRECTORY admin_dat_dir
17 LOCATION (???emp2.dmp???)) ;

Table created.

SQL>
SQL> SELECT * FROM admin_ext_employees2 ;

EMPLOYEE_ID FIRST_NAME LAST_NAME JOB_ID

---

    401 Jesse                Cromwell                  HR_REP    
    402 Abby                 Applegate                 IT_PROG   
    403 Carol                Cousins                   AD_VP     
    404 John                 Richardson                AC_ACCOUNT
    360 Jane                 Janus                     ST_CLERK  
    361 Mark                 Jasper                    SA_REP    
    362 Brenda               Starr                     AD_ASST   
    363 Alex                 Alda                      AC_MGR