Chapter 4: Expressions, Identifiers, and Wildcard Characters

Bitwise operators

The bitwise operators are a Transact-SQL extension for use with integer type data. These operators convert each integer operand into its binary representation, then evaluate the operands column by column. A value of 1 corresponds to true; a value of 0 corresponds to false.

Table 4-3 summarizes the results for operands of 0 and 1. If either operand is NULL, the bitwise operator returns NULL:

**Table 4-3: Truth tables for bitwise operations**
& ( and)	1	0
1	1	0
0	0	0

\| ( or)	1	0
1	1	1
0	1	0

^ (exclusive or)	1	0
1	0	1
0	1	0

~ (not)
1	FALSE
0	0

The examples in Table 4-4 use two tinyint arguments, A = 170 (10101010 in binary form) and B = 75 (01001011 in binary form).

**Table 4-4: Examples of bitwise operations**
Operation	Binary form	Result	Explanation
(A & B)	10101010 01001011 ------------ 00001010	10	Result column equals 1 if both A and B are 1. Otherwise, result column equals 0.
(A \| B)	10101010 01001011 ------------ 11101011	235	Result column equals 1 if either A or B, or both, is 1. Otherwise, result column equals 0
(A ^ B)	10101010 01001011 ------------ 11100001	225	Result column equals 1 if either A or B, but not both, is 1
(~A)	10101010 ------------ 01010101	85	All 1s are changed to 0s and all 0s to 1s

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