Oracle PL/SQL/Subquery/update
Delete and subquery
<source lang="sql">
SQL> SQL> SQL> create table salary
2 ( grade NUMBER(2) constraint S_PK primary key 3 , lowerlimit NUMBER(6,2) 4 , upperlimit NUMBER(6,2) 5 , bonus NUMBER(6,2) 6 , constraint S_LO_UP_CHK check (lowerlimit <= upperlimit) 7 ) ;
Table created. SQL> SQL> insert into salary values (1, 700,1200, 0); 1 row created. SQL> insert into salary values (2, 1201,1400, 50); 1 row created. SQL> insert into salary values (3, 1401,2000, 100); 1 row created. SQL> insert into salary values (4, 2001,3000, 200); 1 row created. SQL> insert into salary values (5, 3001,9999, 500); 1 row created. SQL> SQL> delete from (select *
2 from salary 3 where grade = 5);
1 row deleted. SQL> SQL> drop table salary; Table dropped.
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subquery in update statement
<source lang="sql">
SQL> SQL> CREATE TABLE EMP(
2 EMPNO NUMBER(4) NOT NULL, 3 ENAME VARCHAR2(10), 4 JOB VARCHAR2(9), 5 MGR NUMBER(4), 6 HIREDATE DATE, 7 SAL NUMBER(7, 2), 8 COMM NUMBER(7, 2), 9 DEPTNO NUMBER(2) 10 );
SQL> SQL> INSERT INTO EMP VALUES(7369, "SMITH", "CLERK", 7902,TO_DATE("17-DEC-1980", "DD-MON-YYYY"), 800, NULL, 20); SQL> INSERT INTO EMP VALUES(7499, "ALLEN", "SALESMAN", 7698,TO_DATE("20-FEB-1981", "DD-MON-YYYY"), 1600, 300, 30); SQL> INSERT INTO EMP VALUES(7521, "WARD", "SALESMAN", 7698,TO_DATE("22-FEB-1981", "DD-MON-YYYY"), 1250, 500, 30); SQL> INSERT INTO EMP VALUES(7566, "JONES", "MANAGER", 7839,TO_DATE("2-APR-1981", "DD-MON-YYYY"), 2975, NULL, 20); SQL> INSERT INTO EMP VALUES(7654, "MARTIN", "SALESMAN", 7698,TO_DATE("28-SEP-1981", "DD-MON-YYYY"), 1250, 1400, 30); SQL> INSERT INTO EMP VALUES(7698, "BLAKE", "MANAGER", 7839,TO_DATE("1-MAY-1981", "DD-MON-YYYY"), 2850, NULL, 30); SQL> INSERT INTO EMP VALUES(7782, "CLARK", "MANAGER", 7839,TO_DATE("9-JUN-1981", "DD-MON-YYYY"), 2450, NULL, 10); SQL> INSERT INTO EMP VALUES(7788, "SCOTT", "ANALYST", 7566,TO_DATE("09-DEC-1982", "DD-MON-YYYY"), 3000, NULL, 20); SQL> INSERT INTO EMP VALUES(7839, "KING", "PRESIDENT", NULL,TO_DATE("17-NOV-1981", "DD-MON-YYYY"), 5000, NULL, 10); SQL> INSERT INTO EMP VALUES(7844, "TURNER", "SALESMAN", 7698,TO_DATE("8-SEP-1981", "DD-MON-YYYY"), 1500, 0, 30); SQL> INSERT INTO EMP VALUES(7876, "ADAMS", "CLERK", 7788,TO_DATE("12-JAN-1983", "DD-MON-YYYY"), 1100, NULL, 20); SQL> INSERT INTO EMP VALUES(7900, "JAMES", "CLERK", 7698,TO_DATE("3-DEC-1981", "DD-MON-YYYY"), 950, NULL, 30); SQL> INSERT INTO EMP VALUES(7902, "FORD", "ANALYST", 7566,TO_DATE("3-DEC-1981", "DD-MON-YYYY"), 3000, NULL, 20); SQL> INSERT INTO EMP VALUES(7934, "MILLER", "CLERK", 7782,TO_DATE("23-JAN-1982", "DD-MON-YYYY"), 1300, NULL, 10); SQL> SQL> CREATE TABLE DEPT(
2 DEPTNO NUMBER(2), 3 DNAME VARCHAR2(14), 4 LOC VARCHAR2(13) 5 );
SQL> SQL> INSERT INTO DEPT VALUES (10, "ACCOUNTING", "NEW YORK"); SQL> INSERT INTO DEPT VALUES (20, "RESEARCH", "DALLAS"); SQL> INSERT INTO DEPT VALUES (30, "SALES", "CHICAGO"); SQL> INSERT INTO DEPT VALUES (40, "OPERATIONS", "BOSTON"); SQL> SQL> SQL> alter table dept
2 add emp_count number 3 constraint must_be_between_3_8 4 check(emp_count between 3 and 8 OR emp_count = 0) 5 deferrable initially deferred;
SQL> SQL> update dept set emp_count = (select count(*) from emp where emp.deptno = dept.deptno )
2 /
SQL> SQL> alter table dept
2 modify emp_count NOT NULL;
SQL> SQL> create trigger emp_dept_cnt_trigger
2 after insert or update or delete on emp 3 for each row 4 begin 5 if ( updating and :old.deptno = :new.deptno ) 6 then 7 return; 8 end if; 9 if ( inserting or updating ) 10 then 11 update dept set emp_count = emp_count+1 12 where deptno = :new.deptno; 13 end if; 14 if ( updating or deleting ) 15 then 16 update dept set emp_count = emp_count-1 17 where deptno = :old.deptno; 18 end if; 19 end; 20 /
SQL> SQL> drop table emp; SQL> drop table dept; SQL>
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using subquery in the SET clause of UPDATE statement
<source lang="sql">
SQL> SQL> create table employee(
2 emp_no integer primary key 3 ,lastname varchar2(20) not null 4 ,firstname varchar2(15) not null 5 ,midinit varchar2(1) 6 ,street varchar2(30) 7 ,city varchar2(20) 8 ,state varchar2(2) 9 ,zip varchar2(5) 10 ,zip_4 varchar2(4) 11 ,area_code varchar2(3) 12 ,phone varchar2(8) 13 ,salary number(3) 14 ,birthdate date 15 ,hiredate date 16 ,title varchar2(20) 17 ,dept_no integer 18 ,mgr integer 19 ,region number 20 ,division number 21 ,total_sales number 22 );
Table created. SQL> insert into employee(emp_no, lastname, firstname, midinit, street, city, state, zip,zip_4, area_code, phone, salary, birthdate, hiredate,title, dept_no, mgr, region, division, total_sales)
2 values (1,"Anderson","Nancy","N","33 Ave","London","NY","11111","1111","212","234-1111",3.75,"21-mar-1927","1-feb-1947","Sales Manager",2,null,100,10,40000);
1 row created. SQL> insert into employee(emp_no, lastname, firstname, midinit, street, city, state, zip,zip_4, area_code, phone, salary, birthdate, hiredate,title, dept_no, mgr, region, division, total_sales)
2 values (2,"Last","First","F","12 Ave","Paris","CA","22222","2222","111","867-2222",7.75,"14-feb-1976","15-mar-1985","Sales Clerk",2,1,100,10,10000);
1 row created. SQL> insert into employee(emp_no, lastname, firstname, midinit, street, city, state, zip,zip_4, area_code, phone, salary, birthdate, hiredate,title, dept_no, mgr, region, division, total_sales)
2 values (3,"Wash","Georgia","G","1 Street14","Barton","NJ","33333","3333","214","340-3333",11.50,"2-jul-1977","21-apr-2004","Designer",1,2,100,10,40000);
1 row created. SQL> insert into employee(emp_no, lastname, firstname, midinit, street, city, state, zip,zip_4, area_code, phone, salary, birthdate, hiredate,title, dept_no, mgr, region, division, total_sales)
2 values (4,"Bush","Dave","D","56 Street","Island","RI","44444","4444","215","777-4444",21.65,"15-may-1945","2-aug-1975","Designer",1,2,100,10,40000);
1 row created. SQL> insert into employee(emp_no, lastname, firstname, midinit, street, city, state, zip,zip_4, area_code, phone, salary, birthdate, hiredate,title, dept_no, mgr, region, division, total_sales)
2 values (5,"Will","Robin","W","56 Street","Island","MA","55555","5555","216","777-5555",24.65,"10-dec-1980","2-aug-2007","Designer",1,5,100,10,40000);
1 row created. SQL> insert into employee(emp_no, lastname, firstname, midinit, street, city, state, zip,zip_4, area_code, phone, salary, birthdate, hiredate,title, dept_no, mgr, region, division, total_sales)
2 values (6,"Pete","Mona","M","13 Ave","York","MO","66666","6666","217","111-6666",9,"14-feb-1966","15-mar-1985","Sales Clerk",2,5,100,10,40000);
1 row created. SQL> insert into employee(emp_no, lastname, firstname, midinit, street, city, state, zip,zip_4, area_code, phone, salary, birthdate, hiredate,title, dept_no, mgr, region, division, total_sales)
2 values (7,"Roke","John","J","67 Ave","New York","BC","77777","7777","218","122-7777",10.00,"14-jun-1955","15-mar-1975","Accountant",3,2,100,10,40000);
1 row created. SQL> insert into employee(emp_no, lastname, firstname, midinit, street, city, state, zip,zip_4, area_code, phone, salary, birthdate, hiredate,title, dept_no, mgr, region, division, total_sales)
2 values (8,"Horry","Tedi","T","1236 Lane","Newton","NY","88888","8888","219","222-8888",13.00,"10-jun-1955","15-aug-1985","Sales Representative",3,2,100,10,50000);
1 row created. SQL> insert into employee(emp_no, lastname, firstname, midinit, street, city, state, zip,zip_4, area_code, phone, salary, birthdate, hiredate,title, dept_no, mgr, region, division, total_sales)
2 values (9,"Bar","Candi","C","400 East Street","Yorken","NY","99999","9999","220","321-9999",12.00,"10-oct-1933","15-jan-1969","Sales Representative",3,5,100,10,35000);
1 row created. SQL> SQL> SQL> select * from employee;
EMP_NO LASTNAME FIRSTNAME M
-------------------- --------------- -
STREET CITY ST ZIP ZIP_ ARE
-------------------- -- ----- ---- ---
PHONE SALARY BIRTHDATE HIREDATE
---------- -------------------- --------------------
TITLE DEPT_NO MGR REGION DIVISION
---------- ---------- ---------- ----------
TOTAL_SALES
1 Anderson Nancy N
33 Ave London NY 11111 1111 212 234-1111 4 21-MAR-1927 00:00:00 01-FEB-1947 00:00:00 Sales Manager 2 100 10
40000
2 Last First F
12 Ave Paris CA 22222 2222 111 867-2222 8 14-FEB-1976 00:00:00 15-MAR-1985 00:00:00 Sales Clerk 2 1 100 10
10000
3 Wash Georgia G
1 Street14 Barton NJ 33333 3333 214 340-3333 12 02-JUL-1977 00:00:00 21-APR-2004 00:00:00 Designer 1 2 100 10
40000
4 Bush Dave D
56 Street Island RI 44444 4444 215 777-4444 22 15-MAY-1945 00:00:00 02-AUG-1975 00:00:00 Designer 1 2 100 10
40000
5 Will Robin W
56 Street Island MA 55555 5555 216 777-5555 25 10-DEC-1980 00:00:00 02-AUG-2007 00:00:00 Designer 1 5 100 10
40000
6 Pete Mona M
13 Ave York MO 66666 6666 217 111-6666 9 14-FEB-1966 00:00:00 15-MAR-1985 00:00:00 Sales Clerk 2 5 100 10
40000
7 Roke John J
67 Ave New York BC 77777 7777 218 122-7777 10 14-JUN-1955 00:00:00 15-MAR-1975 00:00:00 Accountant 3 2 100 10
40000
8 Horry Tedi T
1236 Lane Newton NY 88888 8888 219 222-8888 13 10-JUN-1955 00:00:00 15-AUG-1985 00:00:00 Sales Representative 3 2 100 10
50000
9 Bar Candi C
400 East Street Yorken NY 99999 9999 220 321-9999 12 10-OCT-1933 00:00:00 15-JAN-1969 00:00:00 Sales Representative 3 5 100 10
35000
9 rows selected. SQL> SQL> select o.emp_no, o.salary, (select avg(i.salary) * 1.1 from employee i
2 where i.dept_no = o.dept_no) AS dept_avg 3 from employee o 4 order by 1; EMP_NO SALARY DEPT_AVG
---------- ----------
1 4 7.7
2 8 7.7
3 12 21.6333333
4 22 21.6333333
5 25 21.6333333
6 9 7.7
7 10 12.8333333
8 13 12.8333333
9 12 12.8333333
9 rows selected. SQL> SQL> UPDATE employee e1
2 SET e1.salary = 1.1 * 3 (SELECT avg(e2.salary) 4 FROM employee e2 5 WHERE e1.dept_no = e2.dept_no);
9 rows updated. SQL> SQL> select emp_no, salary from employee order by 1;
EMP_NO SALARY
----------
1 8
2 8
3 22
4 22
5 22
6 8
7 13
8 13
9 13
9 rows selected. SQL> SQL> SQL> drop table employee; Table dropped. SQL> --
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