~ (Bitwise NOT) (Transact-SQL)
Applies to: SQL Server (all supported versions) Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics Parallel Data Warehouse
Performs a bitwise logical NOT operation on an integer value.
To view Transact-SQL syntax for SQL Server 2014 and earlier, see Previous versions documentation.
Is any valid expression of any one of the data types of the integer data type category, the bit, or the binary or varbinary data types. expression is treated as a binary number for the bitwise operation.
Only one expression can be of either binary or varbinary data type in a bitwise operation.
int if the input values are int.
smallint if the input values are smallint.
tinyint if the input values are tinyint.
bit if the input values are bit.
The ~ bitwise operator performs a bitwise logical NOT for the expression, taking each bit in turn. If expression has a value of 0, the bits in the result set are set to 1; otherwise, the bit in the result is cleared to a value of 0. In other words, ones are changed to zeros and zeros are changed to ones.
When you perform any kind of bitwise operation, the storage length of the expression used in the bitwise operation is important. We recommend that you use this same number of bytes when storing values. For example, storing the decimal value of 5 as a tinyint, smallint, or int produces a value stored with different numbers of bytes: tinyint stores data using 1 byte; smallint stores data using 2 bytes, and int stores data using 4 bytes. Therefore, performing a bitwise operation on an int decimal value can produce different results from those using a direct binary or hexadecimal translation, especially when the ~ (bitwise NOT) operator is used. The bitwise NOT operation may occur on a variable of a shorter length. In this case, when the shorter length is converted to a longer data type variable, the bits in the upper 8 bits may not be set to the expected value. We recommend that you convert the smaller data type variable to the larger data type, and then perform the NOT operation on the result.
The following example creates a table using the int data type to store the values and inserts the two values into one row.
CREATE TABLE bitwise ( a_int_value INT NOT NULL, b_int_value INT NOT NULL); GO INSERT bitwise VALUES (170, 75); GO
The following query performs the bitwise NOT on the
SELECT ~ a_int_value, ~ b_int_value FROM bitwise;
Here is the result set:
--- --- -171 -76 (1 row(s) affected)
The binary representation of 170 (
0000 0000 1010 1010. Performing the bitwise NOT operation on this value produces the binary result
1111 1111 0101 0101, which is decimal -171. The binary representation for 75 is
0000 0000 0100 1011. Performing the bitwise NOT operation produces
1111 1111 1011 0100, which is decimal -76.
(~A) 0000 0000 1010 1010 ------------------- 1111 1111 0101 0101 (~B) 0000 0000 0100 1011 ------------------- 1111 1111 1011 0100