Is null operator-comparison operators, PL-SQL Programming

Assignment Help:

IS NULL Operator

The IS NULL operator returns the Boolean value TRUE whenever its operand is null or FALSE if it is not null. The comparisons including the nulls always yield NULL. And hence, to test for nullity (the state of being null), then do not use the statement

IF variable = NULL THEN...

Rather, use the statement below:

IF variable IS NULL THEN...

Related Discussions:- Is null operator-comparison operators

Initializing and referencing collections, Initializing and Referencing Coll...

Initializing and Referencing Collections Until you initialize a collection, a nested table or varray is automatically null (i.e. the collection itself is null, not its elements)

Use serially reusable packages - performance of application, Use Serially R...

Use Serially Reusable Packages To help you to manage the use of memory, the PL/SQL gives the pragma SERIALLY_ REUSABLE that mark some packages as serially reusable . So mark

Sql, Write a query to find academics that are authors and that have only ev...

Write a query to find academics that are authors and that have only ever coauthored papers with authors from institutes in the same state as their own. List their academic number,

Object types - syntax, Object Types An object type is a user-defined co...

Object Types An object type is a user-defined complex datatype which encapsulates the data structure along with the functions and procedures required to manipulate the data. Th

Program, heap sort program in pl/sql

heap sort program in pl/sql

Using for update, Using FOR UPDATE If you declare a cursor which will ...

Using FOR UPDATE If you declare a cursor which will be referenced in the CURRENT OF clause of an UPDATE or DELETE statement, you should use the FOR UPDATE clause to obtain an

Rownum - sql pseudocolumns, ROWNUM The ROWNUM returns a number represe...

ROWNUM The ROWNUM returns a number representing the order in which a row was selected from the table. The first row selected has a ROWNUM of 1; the second row has a ROWNUM of

Providing results of queries, Providing Results of Queries Expressing ...

Providing Results of Queries Expressing queries in SQL is the (big) subject. Here I present just a simple example to give you the flavour of things to come in those chapters.

Use of table comparisons - sql, Use of Table Comparisons - SQL Table ...

Use of Table Comparisons - SQL Table comparisons where it is noted that although table expressions cannot be compared, we have TABLE (t) to convert a table expression t into

Example of wrap operator - sql, Example of WRAP Operator - SQL The eff...

Example of WRAP Operator - SQL The effect of Example can be obtained in SQL but note that one needs to write down not only the names of the columns being wrapped but also the

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages