BIT_OR

Declaration

BIT_OR(expr)

Description

Returns the bitwise OR of all bits in expr.

The result type depends on whether the function parameters are evaluated as binary strings or numbers. If the parameter values are binary strings and not hexadecimal literals, bit literals, or NULL literals, binary string evaluation occurs. Otherwise, numeric calculation occurs, and the parameter values are converted to unsigned 64-bit integers as needed.

If no rows match, BIT_OR() returns a neutral value with the same length as the parameter value (all bits set to 0). NULL values do not affect the result unless all values are NULL, in which case the result is a neutral value with the same length as the parameter value.

Examples

CREATE TABLE tbl1 (year YEAR (4), month INT(2)UNSIGNED ZEROFILL, day INT(2) UNSIGNED ZEROFILL);
Query OK, 0 rows affected (0.063 sec)

INSERT INTO tbl1 VALUES(2021,1,1),(2021,1,22),(2021,1,3),(2021,2,2), (2021,2,23),(2021,2,23);
Query OK, 6 rows affected (0.003 sec)
Records: 6  Duplicates: 0  Warnings: 0

SELECT * FROM tbl1;
+------+-------+------+
| year | month | day  |
+------+-------+------+
| 2021 |    01 |   01 |
| 2021 |    01 |   22 |
| 2021 |    01 |   03 |
| 2021 |    02 |   02 |
| 2021 |    02 |   23 |
| 2021 |    02 |   23 |
+------+-------+------+
6 rows in set (0.002 sec)

SELECT year,month,BIT_COUNT(BIT_OR(1<<day)) AS days FROM tbl1 GROUP BY year,month;
+------+-------+------+
| year | month | days |
+------+-------+------+
| 2021 |    01 |    3 |
| 2021 |    02 |    2 |
+------+-------+------+
2 rows in set (0.001 sec)