Using %type-declarations in sql, PL-SQL Programming

Assignment Help:

Using %TYPE

The %TYPE attribute gives the datatype of a variable or the database column. In the example below, the %TYPE gives the datatype of a variable:

credit REAL(7,2);
debit credit%TYPE;

The Variables declared using %TYPE is treated such as those declared using a datatype specifier. For example, given the earlier declarations, the PL/SQL treats debit such as REAL (7, 2) variable. The later example shows that a %TYPE declaration can involve an initialization clause:

balance NUMBER(7,2);
minimum_balance balance%TYPE := 10.00;
The %TYPE attribute is mainly useful when declaring a variable which refer to a database columns. You can reference a table & column, or you can reference an owner, column, table, and as in

my_dname scott.dept.dname%TYPE;

Using the %TYPE to declare my_dname has two merits. Firstly, you do not require knowing the exact datatype of dname. Secondly, when the database definition of the dname changes, the datatype of my_dname change accordingly at the run time.


Related Discussions:- Using %type-declarations in sql

Indeterminacy in sql, Indeterminacy in SQL Some SQL expressions are ac...

Indeterminacy in SQL Some SQL expressions are actually not function invocations at all in the mathematical sense, being indeterminate-invocations operating on identical input

Example of foreign key constraint - sql, Example of Foreign Key Constraint ...

Example of Foreign Key Constraint Example: Alternative formulation for 6.3 as a foreign key constraint ALTER TABLE EXAM_MARK ADD CONSTRAINT Must_be_enrolled_to_take_exam

Overloading method in pl/sql, Overloading: Similar to packaged subprog...

Overloading: Similar to packaged subprograms, methods of the same type can be overloaded. That is, you can use similar name for various methods if their formal parameters diff

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

Iterative control: loop statement, Iterative Control: LOOP  Statements T...

Iterative Control: LOOP  Statements The LOOP statement executes a series of statements multiple times. There are 3 forms of LOOP statements: LOOP, WHILE-LOOP, & FOR-LOOP. LOOP

Cursor attributes in pl sql, Cursor Attributes   The Cursors and curso...

Cursor Attributes   The Cursors and cursor variables have 4 attributes which give you helpful information about the execution of a data manipulation statement. Syntax:

Pl/sql expressions , Pl/SQL Expressions The Expressions are constructed...

Pl/SQL Expressions The Expressions are constructed by using the operands and operators. An operand is a constant, literal, variable, or function call which contributes a value

Insert command in sql, INSERT Command in SQL Loosely speaking, INSERT...

INSERT Command in SQL Loosely speaking, INSERT takes the rows of a given source table and adds them to the specified target table, retaining all the existing rows in the targ

Theory of spontaneous generation - origin of life, THEORY OF SPONTANEOUS GE...

THEORY OF SPONTANEOUS GENERATION - ABIOGENESIS OR AUTOGENESIS - According to this theory, the existing living communities have originated from non-living organic matter with

Projection in sql - correct version, Projection in SQL - correct version ...

Projection in SQL - correct version Student StudentId is enrolled on some course. SELECT DISTINCT StudentId FROM IS_ENROLLED_ON In more complicated examples it is someti

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