It is a procedural extension language (PL) for the structured query language (SQL) and the Oracle relational database. It provides a built-in, interpreted and OS independent programming environment.
Apart from Oracle it also available Times Ten in-memory database and IBM DB2.
The Syntax of PL/SQL is based on ADA and Pascal programming languages. PL/SQL is tightly integrated with SQL.
PL/SQL offers the following −
PL/SQL supports the following −
Structured programming through functions.
Procedures and object-oriented programming.
Development of web applications and server pages.
It defines the type of block (procedure, function, anonymous) and the way it is called, it declares any variables used in the block, it uses variables and other PL/SQL objects to perform actions and handle any problems that arise during execution of the block.
PL/SQL is not case sensitive. It uses the same data-types as SQL like Boolean, record, table, array and LOB. It allows reference data-types %type and %row type.
Given below is an example for the PL/SQL −
DECLARE current_bldg_code VARCHAR2(5); CURSOR location_cursor IS SELECT room, capacity FROM location WHERE bldg_code = current_bldg_code FOR UPDATE of capacity; location_row location_cursor%rowtype; BEGIN current_bldg_code := ‘LIB’; FOR location_row IN location_cursor LOOP UPDATE location Set capacity = capacity +1 WHERE CURRENT OF location_cursor; END LOOP; COMMIT; END;