PL/SQL is a procedural language extension for SQL, the structured query language for managing data in relational databases. It is a high-level language that provides a powerful and flexible way to develop programs that interact with a database.
SQL in PL/SQL
PL/SQL is integrated with SQL, so you can use SQL statements within PL/SQL programs. This allows you to combine the power of SQL with the flexibility and control of procedural programming languages.
PL/SQL Block Structure
PL/SQL is a block-structured language, which means that a PL/SQL program is made up of one or more blocks of code. Each block is a self-contained unit of a PL/SQL program that can be compiled and executed independently.
A basic PL/SQL block has the following structure:
DECLARE -- Declare variables and constants here BEGIN -- Put PL/SQL statements here EXCEPTION -- Handle exceptions here END;
DECLARE section is optional and is used to declare variables and constants that can be used in the PL/SQL block. The
BEGIN section is where you put the PL/SQL statements that make up the main body of the block. The
EXCEPTION section is also optional and is used to handle exceptions that may be raised during the execution of the PL/SQL block.
PL/SQL Control Structure
PL/SQL also supports various control structures, such as loops and conditional statements, that allow you to control the flow of execution in your programs. For example, you can use an
IF statement to execute a block of code only if a certain condition is met, or you can use a
FOR loop to iterate over a collection of data and perform a set of actions for each element in the collection.
PL/SQL Built-in Programs
In addition to the built-in features of the language, PL/SQL also provides a rich set of built-in functions and packages that you can use to perform various tasks, such as string manipulation, date and time handling, and mathematical operations.
Overall, PL/SQL is a powerful and versatile language for developing database-centric applications. By learning the basics of PL/SQL programming, you can unlock the full potential of your relational database and create sophisticated and efficient programs that can manipulate and manage data in a variety of ways.