PL/SQL Control Statements Quiz: Master IF, LOOP, and CASE Statements

Study Notes

Control Structures in PL/SQL

Conditional control allows the program to flow based on a condition, which can be a variable or expression that returns a Boolean value (TRUE, FALSE, or NULL).
There are three forms of IF statements: IF-THEN, IF-THEN-ELSE, and IF-THEN-ELSIF.

IF-THEN Statement

Tests a simple condition; if the condition evaluates to TRUE, one or more lines of code are executed.
If the condition evaluates to FALSE, program control is passed to the next statement after the test.

IF-THEN-ELSE Statement

Similar to IF, except that when the condition evaluates to FALSE, one or more statements following the ELSE are executed.

IF-THEN-ELSIF Statement

An alternative to using nested IF-THEN-ELSE constructs.

Procedural Language Capability of PL/SQL

Consists of procedural language constructs such as conditional statements (if-else statements) and loops like (FOR loops).
Better performance due to processing multiple SQL statements simultaneously as a single block, reducing network traffic.
Error Handling: PL/SQL handles errors or exceptions effectively during the execution of a PL/SQL program.

PL/SQL Control Structures

According to the structure theorem, any computer program can be written using the basic control structures, which can be combined in any way necessary to deal with a given problem.
Conditional Structure tests a condition, and then executes one sequence of statements instead of another, depending on whether the condition is true or false.
Iterative Structure executes a sequence of statements repeatedly as long as a condition holds true.
Sequence Structure simply executes a sequence of statements in the order in which they occur.

Iterative Control

LOOP statements let you execute a sequence of statements multiple times.
There are three forms of LOOP statements: LOOP, WHILE-LOOP, and FOR-LOOP.
LOOP: simplest form of LOOP statement, which encloses a sequence of statements between the keywords LOOP and END LOOP.
WHILE-LOOP: has a condition that is evaluated at the beginning of each iteration; if the condition is true, the statements in the loop are executed.
FOR-LOOP: iterates over a specified range of integers; the range is part of an iteration scheme, which is enclosed by the keywords FOR and LOOP.

Sequential Control

Normally, execution proceeds sequentially within the block of the code.
The sequence can be changed conditionally as well as unconditionally using the GOTO statement.

PL/SQL Exceptions

Pre-defined exceptions: PL/SQL provides many pre-defined exceptions, which are executed when any database rule is violated by a program.
User-defined exceptions: PL/SQL allows you to define your own exceptions according to the need of your program.

SQL%ROWCOUNT Attribute

Returns the number of rows affected by an INSERT, UPDATE, or DELETE statement, or returned by a SELECT INTO statement.
Example: updating the table and increasing the salary of each customer by 500, and using the SQL%ROWCOUNT attribute to determine the number of rows affected.

Description

Test your knowledge of Oracle PL/SQL control statements with this quiz. Learn about conditional statements like IF-THEN-ELSE and LOOP statements in Oracle. This quiz covers topics related to iterative control statements and their usage in Oracle PL/SQL programming.