bit_shift_left
Description
Shifts the binary representation of a numeric expression to the left by a specified number of bits.
This function performs an arithmetic left shift, during which the bit length does not change, 0 is appended to the end, and the high bit remains unchanged. For example, shifting 10101
to the left by one bit results in 11010
.
Syntax
bit_shift_left(value, shift)
Parameters
value
: the value or numeric expression to shift. Supported data types are TINYINT, SMALLINT, INT, BIGINT, and LARGEINT.
shift
: the number of bits to shift. The supported data type is BIGINT.
Return value
Returns a value of the same type as value
.
Usage notes
- If any input parameter is NULL, NULL is returned.
- If
shift
is less than 0, 0 is returned. - Shifting a
value
by0
always results in the originalvalue
. - Shifting
0
by ashift
always results in0
. - If the data type of
value
is numeric but not an integer, that value will be cast to an integer. See Examples. - If the data type of
value
is a string, the value will be cast to an integer if possible. If the value cannot be cast to an integer, it will be processed as NULL. See Examples.
Examples
Use this function to shift numeric values.
SELECT bit_shift_left(2, 1);
+----------------------+
| bit_shift_left(2, 1) |
+----------------------+
| 4 |
+----------------------+
SELECT bit_shift_left(2.2, 1);
+------------------------+
| bit_shift_left(2.2, 1) |
+------------------------+
| 4 |
+------------------------+
SELECT bit_shift_left("2", 1);
+------------------------+
| bit_shift_left('2', 1) |
+------------------------+
| 4 |
+------------------------+
SELECT bit_shift_left(-2, 1);
+-----------------------+
| bit_shift_left(-2, 1) |
+-----------------------+
| -4 |
+-----------------------+