Answer Posted / harinadh bolisetti

PL/SQL allows developers to define their own exceptions.
User can define the error/exception programmatically based on the business rule.

1. Define Exception
---------------------
We need to define the exception before we raise and handle. User Exceptions are defined using keyword EXCEPTION in declaration section of the block.
The syntax is as follows

<exception_name> EXCEPTION ;


2. Raise the Exception
--------------------------
Once the exceptions are defined , they need to be raised anywhere in the body depending upon predefined logic. User exceptions are raised using the keyword RAISE.
Syntax is as shown below

RAISE <exception_name>

3. Handle the Exception.
--------------------------
User exception are handled in the same way predefined exceptions are handled. They are handled in exception block using WHEN .. THEN keyword
Syntax is as shown below

WHEN <exception_name> THEN


example
----------------
DECLARE
low_sal EXCEPTION;
min_sal NUMBER:= 10000;
new_sal NUMBER:= 8000;
BEGIN
INSERT INTO EMP_EXC_DEMO(EMPNO, DEPTNO, SAL)
VALUES (4000,20,new_sal);
IF new_sal < min_sal THEN
RAISE low_sal;
END IF;
commit;
EXCEPTION
WHEN low_sal THEN
Rollback;
DBMS_OUTPUT.PUT_LINE ('Salary is less than '||min_sal);
WHEN OTHERS THEN
DBMS_OUTPUT.PUT_LINE (SQLERRM);
END;

how can we know the number of days between two given dates using mysql? : Sql dba

1048

---

what is top in tsql? : Transact sql

1119

---

Describe types of sql statements?

1058

---

How do sql databases work?

1001

---

what are aggregate and scalar functions? : Sql dba

1057

---

What is schema in sql example?

1183

---

Mention what is the function that is used to transfer a pl/sql table log to a database table?

993

---

what tools available for managing mysql server? : Sql dba

1085

---

What is the difference between microsoft access and sql?

1024

---

what is the command line end user interface - mysql? : Sql dba

981

---

What is the life of an sql statement?

1024

---

How does cross join work in sql?

1018

---

what is error ora-03113: end-of-file on communication channel?

1165

---

What does select * from mean in sql?

3240

---

What makes a good primary key?

1042

---