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

Important distinctions, Important Distinctions The list of important d...

Important Distinctions The list of important distinctions are given below: Value versus variable Syntax versus semantics Variable versus variable reference

Parameter & keyword description - functions, Parameter & Keyword Descriptio...

Parameter & Keyword Description: function_name: The user-defined function is identifying by that keyword. parameter_name: This identifies the formal parameter that

Structure of an object type in pl/sql, Structure of an Object Type: Si...

Structure of an Object Type: Similar to package, an object type has 2 parts: the specification and the body. The specification is the interface to your applications; it declar

Cursors in pl/sql, Cursors The Oracle uses work areas to execute the SQ...

Cursors The Oracle uses work areas to execute the SQL statements and to store process information. A PL/SQL construct known as the cursor. Let's you assume name a work area and

Other monadic - sql, Other monadic - SQL In 2VL there are just 4 (2 2 ...

Other monadic - SQL In 2VL there are just 4 (2 2 ) monadic operators, of which negation is really the only "useful" one. When a third truth value is introduced we have 27 (3 3

Table comparison - sql, Table Comparison - SQL The following definitio...

Table Comparison - SQL The following definitions for relation comparisons: Let r1 and r2 be relations having the same heading. Then: r1 ⊆ r2 is true if every tuple of r1

Effects of null in aggregate operator - sql, Effects of NULL in Aggregate O...

Effects of NULL in Aggregate Operator - SQL Let aggop(x) be an invocation of some aggregate operator aggop in SQL, where x is an expression (usually an open expression) to be

Restriction and and - sql, Restriction and AND - SQL Restriction is av...

Restriction and AND - SQL Restriction is available via the WHERE operator, and so it is in SQL. However, by Example showing how a certain simple restriction can be expressed u

Data types in sql - decimal, Data Types in SQL - Decimal DECIMAL, NUME...

Data Types in SQL - Decimal DECIMAL, NUMERIC, REAL, FLOAT and various other terms for various sets of rational numbers. When these key words are specified for the declared typ

Mixed notation, Mixed Notation The fourth procedure call shows that yo...

Mixed Notation The fourth procedure call shows that you can mix the positional and named notation. In this situation, the first parameter uses the positional notation, & the s

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages