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When AND is used to connect two conditions, each conditional
expression must be true for the condition to be true and the row
retrieved. If any condition within a compound condition is false, the
compound condition is false and the row is not selected.
For example, if you want to retrieve the records of Corporate Division
Departments with a budget under % latex2html id marker 4778
$10,000 you can write the following
compound condition:
DIV = 'CORP' AND BUDGET < 12000
In this example, AND is the logical operator.
Table here illustrates the four possible cases that can
occur with the logical operator AND for the compound condition just
described.
| | Values for | Values for | Condition1 | Condition2 | | |
| | DIV | BUDGET | DIV='CORP' | BUDGET<12000 | Yields | Row Result |
| 1 | CORP | 10500 | True | True | True | Retrieved |
| 2 | CORP | 28000 | True | False | False | Not retrieved |
| 3 | PROD | 11000 | False | True | False | Not retrieved |
| 4 | PROD | 27500 | False | False | False | Not retrieved |
Table: Logical Operator AND
Example:
Based on the above, let's develop a list of departments in the
Corporate Division with a budget under $12,000.
If you enter the statement:
SELECT DNAME, DIV, BUDGET
FROM DEPARTMENT
WHERE DIV = 'CORP' AND BUDGET < 12000 ;
the result displayed will be:
DNAME DIV BUDGET
Supplies and Procurement CORP 10500
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Copyright © Thunderstone Software Last updated: Sun Mar 17 21:14:49 EDT 2013
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