BIT_OR function
The BIT_OR function runs bit-wise OR operations on all of the values in a single integer column or expression. This function aggregates each bit of each binary value that corresponds to each integer value in the expression.
For example, suppose that your table contains four integer values in a column: 3, 7, 10, and 22. These integers are represented in binary form as follows.
| Integer | Binary value |
|---|---|
| 3 | 11 |
| 7 | 111 |
| 10 | 1010 |
| 22 | 10110 |
If you apply the BIT_OR function to the set of integer values, the operation looks
for any value in which a 1 is found in each position.
In this case, a 1 exists in the last five positions for at least one of the
values, yielding a binary result of 00011111; therefore, the function
returns 31 (or 16 + 8 + 4 + 2 + 1).
Syntax
BIT_OR ( [DISTINCT | ALL] expression )
Arguments
- expression
-
The target column or expression that the function operates on. This expression must have an INT, INT2, or INT8 data type. The function returns an equivalent INT, INT2, or INT8 data type.
- DISTINCT | ALL
-
With the argument DISTINCT, the function eliminates all duplicate values for the specified expression before calculating the result. With the argument ALL, the function retains all duplicate values. ALL is the default. For more information, see DISTINCT support for bit-wise aggregations.
Example
The following query applies the BIT_OR function to the LIKES column in a table called USERLIKES and groups the results by the CITY column.
select city, bit_or(likes) from userlikes group by city order by city; city | bit_or --------------+-------- Los Angeles | 127 Sacramento | 255 San Francisco | 255 San Jose | 255 Santa Barbara | 255 (5 rows)
For four of the cities listed, all of the event types are liked by at least one
user (255=11111111). For Los Angeles, all of the event types except
sports are liked by at least one user (127=01111111).
