Declaring objects in pl/sql, PL-SQL Programming

Assignment Help:

Declaring Objects:

You can use the object types wherever built-in types like CHAR or NUMBER can be used. In the block below, you can declare object r of type Rational. Then, you can call the constructor for the object type Rational to initialize the object. The calls assign the values 6 & 8 to attributes num and den, correspondingly.

DECLARE

r Rational;

BEGIN

r := Rational(6, 8);

DBMS_OUTPUT.PUT_LINE(r.num); -- prints 6

You can declare objects as the formal parameters of the functions and procedures. In that way, you can pass objects to the stored subprograms and from one subprogram to the other. In the later illustration, you use the object type Account to specify the datatype of a formal parameter:

DECLARE

...

PROCEDURE open_acct (new_acct IN OUT Account) IS ...

In the illustration below, you can use object type Account to specify the return type of the function:

DECLARE

...

FUNCTION get_acct (acct_id IN INTEGER) RETURN Account IS ...

 


Related Discussions:- Declaring objects in pl/sql

Iterative control:exit statements, EXIT The EXIT statement forces a loop...

EXIT The EXIT statement forces a loop to done unconditionally. Whenever an EXIT statement is encountered, the loop is done immediately and controls the passes to the next statem

Special cases of projection, Special cases of projection This section ...

Special cases of projection This section describes the identity projection, r {ALL BUT}, and the projection on no attributes, r { }, which yields TABLE_DUM when r is empty, ot

Identifiers in pl/sql, Identifiers You use identifiers to name the PL/S...

Identifiers You use identifiers to name the PL/SQL program items and units that include constants, variables, cursors, exceptions, cursor variables, subprograms, and packages.

Defining ref cursor types, Defining REF CURSOR Types To make cursor va...

Defining REF CURSOR Types To make cursor variables, you take 2 steps. At first, you define a REF CURSOR type, and then declare the cursor variables of that type. You can defin

Database values-assignments in pl/sql, Database Values You can use the S...

Database Values You can use the SELECT statement to have the Oracle assign values to a variable. For Each and every item in the select list, there must be a matching, type-compa

How pl/sql resolves the calls? , How Calls Are Resolved? The figure sho...

How Calls Are Resolved? The figure shows that how the PL/SQL compiler resolves the subprogram calls. When the compiler encounters the procedure or function call, it tries to di

Effects of null for union - sql, Effects of NULL for union - SQL The ...

Effects of NULL for union - SQL The treatment of NULL in invocations of EXCEPT is as for UNION. This is different from its treatment in those of NOT IN and quantified compari

Named notation, Named Notation The second procedure call uses the name...

Named Notation The second procedure call uses the named notation. An arrow (=>) serve as the relationship operator that associates the formal parameter to the left of the arro

Package utl file in pl/sql, UTL_FILE: The Package UTL_FILE permits you...

UTL_FILE: The Package UTL_FILE permits your PL/SQL programs to read & write operating system (OS) text files. It gives a restricted version of the standard OS stream file I/O,

Packaging cursors, Packaging Cursors   You can split a cursor specific...

Packaging Cursors   You can split a cursor specification from its body for placement in a package. In that way, you can change the cursor body without changing the cursor spec

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd