Lesson 3 | PL/SQL variables |
Objective | Identify the Different Types of PL/SQL Variables. |
Identify Different Types of PL/SQL Variables
Variables can be used to store the results of a query for later processing or to calculate values to insert into Oracle database tables.
PL/SQL variables can be used anywhere in an expression, either in SQL or in PL/SQL statements. A variable must be declared before referencing it in other statements, including other declarative statements.
Use the following Slide Show to learn more about PL/SQL variables.
Declaring PL/SQL Variables
A PL/SQL variable can have
- any SQL data type (such as CHAR, DATE, or NUMBER) or
- a PL/SQL- only data type (such as BOOLEAN or PLS_INTEGER).
One has a PL/SQL-only data type; the others have SQL data types.
Oracle Database PL/SQL Programming
PL/SQL Variable Declarations
SQL> DECLARE
2 part_number NUMBER(6); -- SQL data type
3 part_name VARCHAR2(20); -- SQL data type
4 in_stock BOOLEAN; -- PL/SQL-only data type
5 part_price NUMBER(6,2); -- SQL data type
6 part_description VARCHAR2(50); -- SQL data type
7 BEGIN
8 NULL;
9 END;
10 /
PL/SQL procedure successfully completed.
SQL>
Procedure Language SQL
As you have seen, variables provide you with a medium for manipulating data.
In the next lesson, the different variable datatypes will be discussed.