Order of evaluation-pl/sql expressions , PL-SQL Programming

Assignment Help:

Order of Evaluation

When you do not use the parentheses to specify the order of evaluation, the operator precedence determine the order. Now compare the expressions below:

NOT (valid AND done)         |       NOT valid AND done


When the Boolean variables valid and complete the value FALSE, the first expression yields TRUE. Though, the second expression yields FALSE as NOT has a higher precedence than AND. So, the second expression is equivalent to:

(NOT valid) AND done
In the example below, notice that if valid has the value FALSE, the entire expression yields FALSE regardless of the value of done:

valid AND done

Similarly, in the next illustration, when valid has the value TRUE, the entire expression yields TRUE regardless of the value of done:

valid OR done


Related Discussions:- Order of evaluation-pl/sql expressions

I want to build website for funding, Project Description: I want to rebu...

Project Description: I want to rebuild it and add better content to it It will include up to 5 forms The data will be saved on SQL server and the data access layer could b

Data types in sql - character, Data Types in SQL - Character CHARACTER...

Data Types in SQL - Character CHARACTER or, synonymously, CHAR, for character strings. When this type is to be the declared type of something (e.g., a column), the permissible

Using operator deref - manipulating objects in pl sql, Using Operator DEREF...

Using Operator DEREF: You cannot navigate through refs within the PL/SQL procedural statements. Rather than, you should use the operator DEREF in the SQL statement. The DEREF

Using raise_application_error - user-defined exceptions, Using raise_applic...

Using raise_application_error The Package DBMS_STANDARD that is supplied with Oracle gives language facilities that help your application to interact with Oracle. For illustra

How transactions guard your database, How Transactions Guard Your Database ...

How Transactions Guard Your Database The transaction is a sequence of SQL data manipulation statements which does a logical unit of work. The Oracle treats the sequence of SQL

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

Execute privilege, EXECUTE Privilege To call an invoker-rights routine ...

EXECUTE Privilege To call an invoker-rights routine straightforwardly, the users should have the EXECUTE privilege on that routine. By yielding the privilege, you permit a user

Expressions - syntax, Expressions   An expression is a randomly comple...

Expressions   An expression is a randomly complex combination of the constants, variables, literals, operators, & function calls. The simplest expression is the single variabl

Logical operators-pl/sql expressions , Logical Operators The logical op...

Logical Operators The logical operators AND, NOT, and OR follow the tri-state logic shown in table below. The AND and OR are binary operators; NOT is a unary operator.

Albeit simple method , Albeit simple method : These all the truth tabl...

Albeit simple method : These all the truth tables give us our first as albeit simple method for proving a theorem: where check whether it can be written in propositional logic

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