Rephrase conditional control statements, PL-SQL Programming

Assignment Help:

Rephrase Conditional Control Statements

When computing a logical expression, the PL/SQL uses short-circuit evaluation. That is, the PL/SQL stops evaluating the expression as soon as the result can be determined. For illustration, in the OR expression below, when the value of sal is less than 1500, the left operand yields TRUE, Therefore PL/SQL need not evaluate the right operand (as OR returns TRUE if either of its operands is true):

IF (sal < 1500) OR (comm IS NULL) THEN

...

END IF;

Now, consider the AND expression shown below:

 

IF credit_ok(cust_id) AND (loan < 5000) THEN

...

END IF;

The Boolean function credit_ok is forever called. Though, if you switch the operands of AND as shown:

 

IF (loan < 5000) AND credit_ok(cust_id) THEN

...

END IF;

The function is called only if the expression loan < 5000 is true (as AND returns TRUE only if both its operands are true). The similar idea applies to the EXIT-WHEN statements.


Related Discussions:- Rephrase conditional control statements

Assignment source not a literal - variable, Assignment Source Not a Literal...

Assignment Source Not a Literal - Variable Syntax: SET SN = SID (SUBSTRING (SN.C FROM 1 FOR 1)||'5');

Fetching with a cursor, Fetching with a Cursor The FETCH statements re...

Fetching with a Cursor The FETCH statements retrieve the rows in the result set one at a time. After each and every fetch, the cursor advance to the next row in the result set

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

Package specification in pl/sql , Package Specification The package sp...

Package Specification The package specifications contain the public declarations. The scopes of these declarations are local to your database representation and global to the

Inner join, Inner Join We have learned how to retrieve data from one t...

Inner Join We have learned how to retrieve data from one table by using SELECT statement. But, as we have learned, normalized relational databases mean the data is spread betw

For-loop -iterative control, FOR-LOOP While the number of iterations thr...

FOR-LOOP While the number of iterations through a WHILE loop is unknown till the loop completes, then the number of iterations through a FOR loop is known before the loop is ent

Data abstraction, Data Abstraction The Data abstraction extracts the im...

Data Abstraction The Data abstraction extracts the important properties of data while ignoring the not necessary details. Once you design a data structure, you can fail to reme

Table literals - sql, Table Literals - SQL One might expect SQL to sup...

Table Literals - SQL One might expect SQL to support table literals in the manner illustrated in Example 2.2, but in fact that is not a legal SQL expression. Example: Not a

Sql script to create and populate the tables, Create the four tables and po...

Create the four tables and populate them with the given data. Answer the following queries in SQL. 1. Get all part-color/part-city combinations. Note: Here and subsequently, the

Maintain an audit trail of product table changes, The accuracy of product t...

The accuracy of product table data is critical and the Brwebean's. owner wants to have an audit file that contains information regarding all DML activity on the BB_PRODUCT table. T

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