IN Operator

The operator IN tests the set membership. This means "equal to any member of." The set may have nulls, but they are ignored. For illustration, the statement below does not delete the rows in which the ename column is null:

DELETE FROM emp WHERE ename IN (NULL, ’KING’, ’FORD’);

Moreover, the expressions of the form

value NOT IN set

yield FALSE when  the set contains a null. For illustration, instead of deleting the rows in which the ename column is not null and not ’KING’, the statement below deletes no rows:


DELETE FROM emp WHERE ename NOT IN (NULL, ’KING’);


Concatenation Operator

The Double vertical bars (||) serve as the concatenation operator that appends one string to another. For illustration, the expression

’suit’ || ’case’

returns the value as shown below:

’suitcase’

If both the operands have datatype CHAR, the concatenation operator returns a CHAR value. Or else, it returns a VARCHAR2 value.

Posted Date: 10/3/2012 5:33:44 AM | Location : United States

Ask an Expert

Related Discussions:- In operator-comparison operators, Assignment Help, Ask Question on In operator-comparison operators, Get Answer, Expert's Help, In operator-comparison operators Discussions

Write discussion on In operator-comparison operators
Your posts are moderated

Write your message here..

Related Questions

Closing a cursor variable, Closing a Cursor Variable The CLOSE stateme... Closing a Cursor Variable The CLOSE statement disables the cursor variable. After that, the related result set is undefined. The syntax for the same is as shown below: CLOS

Controlling cursor variables, Controlling Cursor Variables You use 3 s... Controlling Cursor Variables You use 3 statements to control the cursor variable: OPEN-FOR, FETCH, & CLOSE. At First, you OPEN a cursor variable FOR a multi-row query. Then, y

Accessing attributes in pl sql, Accessing Attributes: You can refer to ... Accessing Attributes: You can refer to an attribute only by its name not by its position in the object type. To access or modify the value of an attribute, you can use the dot

Begin parameter description in pl sql, BEGIN Parameter Description in pl sq... BEGIN Parameter Description in pl sql: BEGIN: This keyword signals the beginning of the executable section of a PL/SQL block, that contains executable statements. The execut

Varrays versus nested tables, Varrays versus Nested Tables The Nested ta... Varrays versus Nested Tables The Nested tables are differing from varrays in the following ways: 1)  Varrays have a maximum size, while nested tables do not. 2)  Varrays are

Wrapping and unwrapping in sql, Wrapping and unwrapping in SQL Operato... Wrapping and unwrapping in SQL Operators WRAP and UNWRAP in connection with attributes whose declared types are tuple types. Example shows how extension and projection can be

In mode - parameter modes, IN Mode An IN parameter pass the values to ... IN Mode An IN parameter pass the values to the subprogram being called. Within the subprogram, an IN parameter acts like a constant. And hence, it cannot be assigned a value.

Updating by replacement, Updating by replacement Syntax: UPDAT... Updating by replacement Syntax: UPDATE ENROLMENT SET Name = 'Ann' WHERE StudentId = SID ('S1'); Note the use of SET, as already noted in connection with direct a

Like operator-comparison operators, LIKE Operator You use the LIKE opera... LIKE Operator You use the LIKE operator to compare the character value to a pattern. The Case is significant. LIKE returns the Boolean value TRUE when the character patterns mat

What are decision support systems, (a) What are decision support systems, a... (a) What are decision support systems, and what role do they play in the business environment? (b) Data warehousing is defined as "a subject-oriented, integrated, non-volatile c