Beginning Microsoft SQL Server 2008 ... - S3 Tech Training

Chapter 3: The Foundation Statements of T-SQL
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This time we’ve gotten back precisely what we wanted — nothing more, nothing less. In addition, this
query runs much faster than the first query.
Let’s take a look at all the operators we can use with the WHERE clause:
Operator Example Usage Effect
=,
>,
=,
,
!<
AND,
OR,
NOT
=
= ‘Bob’
= AND
>=
!= “MyLiteral”
OR =
“MyOtherLiteral”
Standard comparison operators, these work
as they do in pretty much any programming
language with a couple of notable points:
1. What constitutes “greater than,” “less than,”
and “equal to” can change depending on the
collation order you have selected. (For example,
“ROMEY” = “romey” in places where caseinsensitive
sort order has been selected, but
“ROMEY” < > “romey” in a case-sensitive
situation.)
2. != and both mean “not equal.” !< and !>
mean “not less than” and “not greater than,”
respectively.
Standard boolean logic. You can use these to
combine multiple conditions into one WHERE
clause. NOT is evaluated first, then AND, then OR. If
you need to change the evaluation order, you can
use parentheses. Note that XOR is not supported.
BETWEEN BETWEEN 1 AND 5 Comparison is TRUE if the first value is
between the second and third values inclusive.
It is the functional equivalent of A>=B AND
A