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

Closest approximation to relational union - sql, Closest Approximation to R...

Closest Approximation to Relational Union - SQL Actually, just as SQL has several varieties of JOIN, it also has several varieties of UNION, none of which is equivalent to th

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

Definition of from - sql, Definition of FROM - SQL Recall that the ope...

Definition of FROM - SQL Recall that the operand of FROM is denoted by a commalist, each element of that commalist being a table expression optionally accompanied by a range v

Use tsql function sql server 2012, I want someone to write a TSQL function ...

I want someone to write a TSQL function that returns the name of the ODBC DSN. I will use the queries below, to get information about the connection, but none of these return th

Collections in pl sql, Collections:   The collection is an ordered gr...

Collections:   The collection is an ordered group of elements, all of similar type (for illustration, the grades for a class of students). Each element has an exclusive subsc

Effects of null for table expression, Effects of NULL for Table Expression ...

Effects of NULL for Table Expression Here's an important distinction between expressions denoting tables and expressions denoting multisets of rows: a table expression cannot

Semijoin and composition - sql, Semijoin and Composition - SQL For sem...

Semijoin and Composition - SQL For semijoin, the dyadic relational operator MATCHING, defined thus: r1 MATCHING r2, where r1 and r2 are relations such that r1 JOIN r2 is de

Using not null-declarations in sql, Using NOT NULL Besides assigning an ...

Using NOT NULL Besides assigning an initial value, the declarations can impose the NOT NULL constraint, as the example below shows: acct_id INTEGER(4) NOT NULL := 9999; You ca

Long and long raw in pl/sql, LONG and LONG RAW You use the LONG datatyp...

LONG and LONG RAW You use the LONG datatype to store the variable-length character strings. The LONG datatype is such as the VARCHAR2 datatype, except that the maximum length o

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

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