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

Procedures - syntax, Procedures The procedure is a subprogram which can...

Procedures The procedure is a subprogram which can take parameters and be invoked. Normally, you can use a procedure to perform an action. The procedure has 2 sections: the spe

Sql queries, SELECT a.child_fname,a.child_lname,concat(b.parent_title,b.par...

SELECT a.child_fname,a.child_lname,concat(b.parent_title,b.parent_fname), b.parent_lname,b.parent_tphone FROM child a,parent b WHERE a.parent_id=b.parent_id ORDER BY a.child_fnam

Example of except operator - sql, Example of EXCEPT Operator - SQL Ex...

Example of EXCEPT Operator - SQL Example, like its counterpart in the theory book, illustrates the convenience of allowing any table expression to be the source for an INSERT

Conditionals - sql, Conditionals - SQL At first sight SQL does not app...

Conditionals - SQL At first sight SQL does not appear to have a single operator for expressing logical implication. In this respect it would be in common with most programming

Declaring subprograms, Declaring Subprograms   You can declare subprog...

Declaring Subprograms   You can declare subprograms in any PL/SQL subprogram, block, or package. But, you should declare subprograms at the end of the declarative part after a

Variables and constants in pl/sql, V ariables and Constants in PL/SQL ...

V ariables and Constants in PL/SQL The PL/SQL permits you to declare constants and variables, and then use them in SQL and procedural statements anywhere in the expression. Th

Procedure, 1. Create a procedure called TAX_COST_SP to accomplish the tax c...

1. Create a procedure called TAX_COST_SP to accomplish the tax calculation task. Keep in mind that the state and subtotal values are inputs into the procedure and the procedure is

Use triggers to maintain referential integrity, At times, Brewbean's has ch...

At times, Brewbean's has changed the id number for existing products. In the past, they have had to add a new product row with the new id to the BB_PRODUCT table, modify all the co

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

Query optimization, 1.( /5 marks) Suppose that a B+-tree index with the sea...

1.( /5 marks) Suppose that a B+-tree index with the search key (dept_name, building) is available on relation department. What would be the best way to handle the following selecti

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