1. Chapter 03
DBMS

12. TYPES OF OPERATORS ARTHEMATIC OPERATORS LOGICAL OPERATORS
COMPARISON OPERATORS

13. TYPES OF OPERATORS

15. AND OPERATOR
SQL> SELECT * FROM EMP WHERE COMM = 300 AND DEPTNO = 30;
EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO
7499 ssssd SALESMAN FEB

16. OR OPERATOR 1* SELECT * FROM EMP WHERE COMM = 300 OR DEPTNO = 30
SQL> /
EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO
7499 ssssd SALESMAN FEB
7521 ssssd SALESMAN FEB
7654 ssssd SALESMAN SEP
7698 ssssd MANAGER MAY
7844 ssssd SALESMAN SEP
7900 ssssd CLERK DEC
6 rows selected.

17. NOT OPERATOR 1* SELECT * FROM EMP WHERE NOT COMM = 300 SQL> /
EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO
7521 ssssd SALESMAN FEB
7654 ssssd SALESMAN SEP
7844 ssssd SALESMAN SEP

18. TYPES OF COMPARISON OPERATORS
SYMBOLIC OPERATORS
<,>,<=,>=,=,!=
WORD COMPARISON OPERATORS
LIKE
NOT LIKE IN
NOT IN
BETWEEN
NOT BETWEEN
IS NULL
IS NOT NULL

19. Character functions SQL> select initcap('school') from dual; INITCA
------
School

20. Character functions
SQL> select translate('school','o','m')from dual;
TRANSL
------
schmml

21. Character functions 1* select replace('school','o','mtf')from dual
SQL> /
REPLACE('S
schmtfmtfl

22. Character functions SQL> select substr('school',2,3) from dual; SUB
---
cho

23. Character functions 1* select empno || ' is from ' || deptno from emp
SQL> /
EMPNO||'ISFROM'||DEPTNO
7369 is from 20
7499 is from 30
7521 is from 30
7566 is from 20
7654 is from 30
7698 is from 30
7782 is from 10
14 rows selected.

24. Numeric functions SQL> select ceil(89.77),floor(89.77) from dual;

25. Numeric functions
SQL> select round(89.66,1),trunc(89.66,1) from dual;
ROUND(89.66,1) TRUNC(89.66,1)

26. Numeric functions SQL> select power(2,3) from dual; POWER(2,3) 8

28. If then else SQL> declare 2 a number := 10; 3 b number := 20;
4 c number := 30;
5 begin
6 if a < b then
dbms_output.put_line('a is lesser');
8 else if a < c then
dbms_output.put_line('a is less');
else if b<c then
dbms_output.put_line('b is lesser than c');
12 end if;
13 end if;
14 end if;
15 end;
16 /
a is lesser
PL/SQL procedure successfully completed.

29. Syntax Simple Loop
Loop
<Sequence of Statements >
End Loop;

30. Simple Loop Dec lare v_a number := 0; begin Loop v_a := v_a+2;
dbms_output.put_line(' The value for v_a is'|| v_a);
exit when v_a >= 10;
End Loop;
dbms_output.put_line('End of Loop');
End; /

31. Simple Loop Demo SQL> @loopdemo Input truncated to 1 characters
PL/SQL procedure successfully completed.
SQL> set serveroutput on;
SQL> @loopdemo
The value for v_a is 2
The value for v_a is 4
The value for v_a is 6
The value for v_a is 8
The value for v_a is 10
End of Loop

32. Syntax While loop While<condition> Loop
<Sequence of Statements >
End Loop;

33. While loop demo declare v_a number := 0; begin while(v_a <= 10)
dbms_output.put_line(' The value for v_a is'|| v_a);
v_a := v_a+2;
End Loop;
dbms_output.put_line('End of Loop');
End; /

34. While loop SQL> @loopdemo Input truncated to 1 characters
The value for v_a is 0
The value for v_a is 2
The value for v_a is 4
The value for v_a is 6
The value for v_a is 8
The value for v_a is 10
End of Loop
PL/SQL procedure successfully completed.

35. For Loop declare v_a number ; begin for v_a in 1..10 Loop
dbms_output.put_line(' The value for v_a is'|| v_a);
End Loop;
dbms_output.put_line('End of Loop');
End; /

36. For Loop SQL> @loopdemo; Input truncated to 1 characters
The value for v_a is1
The value for v_a is2
The value for v_a is3
The value for v_a is4
The value for v_a is5
The value for v_a is6
The value for v_a is7
The value for v_a is8
The value for v_a is9
The value for v_a is10
End of Loop
PL/SQL procedure successfully completed.

37. Explicit Cursor

38. Cursor DECLARE emp_rec emp%rowtype; CURSOR emp_cur IS
SELECT * FROM emp
WHERE sal > 1000;
BEGIN
IF NOT emp_cur%ISOPEN THEN
OPEN emp_cur;
End if;
FETCH emp_cur INTO emp_rec;
dbms_output.put_line (emp_rec.ename || ' ' || emp_rec.sal);
CLOSE emp_cur;
END; /

39. Output
ALLEN 1600

40. DECLARE
emp_rec emp%rowtype;
CURSOR emp_cur IS
SELECT * FROM emp
WHERE sal > 1000;
BEGIN
IF NOT emp_cur%ISOPEN THEN
OPEN emp_cur;
End if;
Loop
FETCH emp_cur INTO emp_rec;
EXIT WHEN emp_cur%NOTFOUND;
dbms_output.put_line (emp_rec.ename || ' ' || emp_rec.sal);
End Loop;
CLOSE emp_cur;
END;

41. Output SQL> @curdemo; ALLEN 1600 WARD 1250 JONES 2975 MARTIN 1250
BLAKE 2850
CLARK 2450
SCOTT 3000
KING 5000
TURNER 1500
ADAMS 1100
FORD 3000
MILLER 1300
PL/SQL procedure successfully completed.

42. EXCEPTIONS SYNTAX (GENERAL FORM) Declare =declarations Begin
=executable statements
Exception
= Exception handlers.

43. Exception Exception when <Exception name> then
<user defined action to be carried on>
End;

44. Example SQL> select * from account; ACC_NO CUST_NAME BALANCE
1 misha
2 minu
3 sheeba

45. Exception declare current_balance account.balance%type;
Account_no account.acc_no%type;
less_bal exception;
v_acc number := &v_acc;
v_withdrawal number := & v_withdrawal;
begin
Select balance,Acc_no into current_balance,Account_no from account
where acc_no = v_acc;
if (current_balance - v_withdrawal <= 500) then
raise less_bal;
else
update account
set balance = balance-v_withdrawal
dbms_output.put_line('withdraw success');
end if;
Exception
when less_bal then
dbms_output.put_line('sorry');
End; /

46. Exception SQL> @errdemo Enter value for v_acc: 1
old 5: v_acc number := &v_acc;
new 5: v_acc number := 1;
Enter value for v_withdrawal: 500
old 6: v_withdrawal number := & v_withdrawal;
new 6: v_withdrawal number := 500;
sorry
PL/SQL procedure successfully completed.

47. Exception SQL> / Enter value for v_acc: 2
old 5: v_acc number := &v_acc;
new 5: v_acc number := 2;
Enter value for v_withdrawal: 500
old 6: v_withdrawal number := & v_withdrawal;
new 6: v_withdrawal number := 500;
withdraw success
PL/SQL procedure successfully completed.
SQL> select * from account
2 ;
ACC_NO CUST_NAME BALANCE
1 misha
2 minu
3 sheeba

48. System defined Exception
SQL> set serveroutput on SQL> SQL> DECLARE   2          Num_a NUMBER := 6;   3          Num_b NUMBER;   4  BEGIN   5          Num_b := 0;   6          Num_a := Num_a / Num_b;   7          Num_b := 7;   8          dbms_output.put_line(' Value of Num_b ' || Num_b);   9  EXCEPTION  10          WHEN ZERO_DIVIDE  11  THEN  12                dbms_output.put_line('Trying to divide by zero');  13                dbms_output.put_line(' Value of Num_a ' || Num_a);  14                dbms_output.put_line(' Value of Num_b ' || Num_b);  15  END;  16  / Trying to divide by zero Value of Num_a 6 Value of Num_b 0 PL/SQL procedure successfully completed.

49. Views 2 as 3* select empno,sal from emp SQL> / View created.
1 create view view_v1
2 as
3* select empno,sal from emp
SQL> /
View created.
SQL> select * from view_v1;
EMPNO SAL

50. sequence 1 create sequence s1 2 increment by 1 3 start with 1
4 maxvalue 10
5 minvalue 1
6 cycle
7* cache 9
SQL> /
Sequence created.
SQL> insert into stud values(s1.nextval,'meena',90);
1 row created.
SQL> select * from stud;
ROLLNO NAME MARKS
1 meena

51. indexes SQL> select rowid from emp; ROWID ------------------
AAAAeFAACAAAAEbAAA
AAAAeFAACAAAAEbAAB
AAAAeFAACAAAAEbAAC
AAAAeFAACAAAAEbAAD
AAAAeFAACAAAAEbAAE
AAAAeFAACAAAAEbAAF
AAAAeFAACAAAAEbAAG
AAAAeFAACAAAAEbAAH
AAAAeFAACAAAAEbAAI

52. synonym SQL> create synonym emp1 for emp; Synonym created.
SQL> select * from emp1;
EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO
7369 ssssd CLERK DEC
7499 ssssd SALESMAN FEB
7521 ssssd SALESMAN FEB
7566 ssssd MANAGER APR
7654 ssssd SALESMAN SEP
7698 ssssd MANAGER MAY
7782 ssssd MANAGER JUN
7788 ssssd ANALYST APR