PL/SQL User's Guide and Reference

Defining Collection Types
DECLARE
TYPE EmpTabTyp IS TABLE OF emp%ROWTYPE
INDEX BY BINARY_INTEGER;
emp_tab EmpTabTyp;
BEGIN
/* Retrieve employee record. */
SELECT * INTO emp_tab(7468) FROM emp WHERE empno = 7468;
END;
Defining SQL Types Equivalent to PL/SQL Collection Types
To store nested tables and varrays inside database tables, you must also declare SQL
types using the CREATE TYPE statement. The SQL types can be used as columns or
as attributes of SQL object types.
You can declare equivalent types within PL/SQL, or use the SQL type name in a
PL/SQL variable declaration.
Nested Table Example
The following SQL*Plus script shows how you might declare a nested table in SQL,
and use it as an attribute of an object type:
CREATE TYPE CourseList AS TABLE OF VARCHAR2(10) -- define type
/
CREATE TYPE Student AS OBJECT ( -- create object
id_num INTEGER(4),
name VARCHAR2(25),
address VARCHAR2(35),
status CHAR(2),
courses CourseList) -- declare nested table as attribute
/
The identifier courses represents an entire nested table. Each element of courses
will store the code name of a college course such as ’Math 1020’.
Varray Example
The script below creates a database column that stores varrays. Each varray element
contains a VARCHAR2.
-- Each project has a 16-character code name.
-- We will store up to 50 projects at a time in a database column.
CREATE TYPE ProjectList AS VARRAY(50) OF VARCHAR2(16);
/
PL/SQL Collections and Records 5-9