What is case in PL SQL?

The PL/SQL CASE statement facilitates you to execute a sequence of satatements based on a selector. A CASE statement is evaluated from top to bottom. If it get the condition TRUE, then the corresponding THEN calause is executed and the execution goes to the END CASE clause.

What are the two types of CASE statement in PL SQL?

The CASE statement has two types: simple CASE statement and searched CASE statement. Both types of the CASE statements support an optional ELSE clause.

How can we define and execute PL SQL CASE statement?

The PL/SQL CASE statement evaluates the selector only once to decide which sequence of statements to execute. Followed by the selector is any number of the WHEN clauses. If the selector value is equal to expression in the WHEN clause, the corresponding sequence of statement after the THEN keyword is executed.

Can we use case in Plsql?

The CASE statement can be used in Oracle/PLSQL. SELECT table_name, CASE WHEN owner=’SYS’ THEN ‘The owner is SYS’ WHEN owner=’SYSTEM’ THEN ‘The owner is SYSTEM’ ELSE ‘The owner is another value’ END FROM all_tables; With the ELSE clause omitted, if no condition was found to be true, the CASE statement would return NULL.

How does PL SQL work?

PL/SQL includes procedural language elements such as conditions and loops. It allows declaration of constants and variables, procedures and functions, types and variables of those types, and triggers. It can handle exceptions (run-time errors). Arrays are supported involving the use of PL/SQL collections.

Where are exceptions used in PL SQL?

An error occurs during the program execution is called Exception in PL/SQL. PL/SQL facilitates programmers to catch such conditions using exception block in the program and an appropriate action is taken against the error condition. There are two type of exceptions: System-defined Exceptions.

How many types of variables scopes are present in PL SQL?

Variable Scope in PL/SQL: There are two types of variable scope: Local Variable: Local variables are the inner block variables which are not accessible to outer blocks. Global Variable: Global variables are declared in outermost block.

How do you write a switch case in PL SQL?

Syntax: CASE (expression) WHEN THEN action_blockl; WHEN THEN action_block2; WHEN THEN action_block3; ELSE action_block_default; END CASE; In the above syntax, the expression will return a value that could be of any type (variable, number, etc.).

Is PL SQL good for Career?

PL SQL is an integrated and high-performance database language that can work well with other languages like C++, Java, and C#. However, if you want to write a code that is going to interact with Oracle database, there is no better language than PL SQL for this job.

How do you handle exceptions in PL SQL?

An exception is a PL/SQL error that is raised during program execution, either implicitly by TimesTen or explicitly by your program. Handle an exception by trapping it with a handler or propagating it to the calling environment.