Transact-SQL Boolean Constants



Databases and other programming environments provide operators you can use to perform data analysis. The operators used are called logical operators because they are used to perform comparisons that produce a result of true or false (there is no middle result; in other words, something is not half true or half false or "Don't Know": either it is true or it is false).

The TRUE and FALSE Constants

In Boolean algebra, something is considered TRUE when it holds a value. The value is also considered as 1 or Yes. By contrast, if something doesn't hold a value, it is considered non-existent and non-worthy of consideration. Such a thing has a value of FALSE, 0, or No. To retrieve such a value, you can just find out if the value of a field is existent or not.

The comparison for a True or False value is mostly performed on Boolean fields, such a case is the SPHome (which specifies whether a student lives in a single parent home) field of the Students table of the HighSchool database. If a record has a value of 1, the table considers that such a field is True. If the field has a 0 value, then it holds a FALSE value.


Home Copyright © 2007-2009 FunctionX, Inc.