BITMAP_OR_COUNT
Description
Computes the union of two or more input Bitmaps and returns the count of elements in the union.
Syntax
BITMAP_OR_COUNT(<bitmap1>, <bitmap2>, ..., <bitmapN>)
Parameters
| Parameter | Description |
|---|---|
<bitmap1> | The first Bitmap |
<bitmap2> | The second Bitmap |
| ... | ... |
<bitmapN> | The N-th Bitmap |
Return Value
The count of elements in the union of multiple Bitmaps.
Returns NULL if any of the Bitmaps is NULL.
Examples
To compute the count of elements in the union of a non-empty Bitmap and an empty Bitmap:
select bitmap_or_count(bitmap_from_string('1,2,3'), bitmap_empty());
The result will be:
+--------------------------------------------------------------+
| bitmap_or_count(bitmap_from_string('1,2,3'), bitmap_empty()) |
+--------------------------------------------------------------+
| 3 |
+--------------------------------------------------------------+
To compute the count of elements in the union of two identical Bitmaps:
select bitmap_or_count(bitmap_from_string('1,2,3'), bitmap_from_string('1,2,3'));
The result will be:
+---------------------------------------------------------------------------+
| bitmap_or_count(bitmap_from_string('1,2,3'), bitmap_from_string('1,2,3')) |
+---------------------------------------------------------------------------+
| 3 |
+---------------------------------------------------------------------------+
To compute the count of elements in the union of two different Bitmaps:
select bitmap_or_count(bitmap_from_string('1,2,3'), bitmap_from_string('3,4,5'));
The result will be:
+---------------------------------------------------------------------------+
| bitmap_or_count(bitmap_from_string('1,2,3'), bitmap_from_string('3,4,5')) |
+---------------------------------------------------------------------------+
| 5 |
+---------------------------------------------------------------------------+
To compute the count of elements in the union of multiple Bitmaps, including an empty Bitmap:
select bitmap_or_count(bitmap_from_string('1,2,3'), bitmap_from_string('3,4,5'), to_bitmap(100), bitmap_empty());
The result will be:
+-----------------------------------------------------------------------------------------------------------+
| bitmap_or_count(bitmap_from_string('1,2,3'), bitmap_from_string('3,4,5'), to_bitmap(100), bitmap_empty()) |
+-----------------------------------------------------------------------------------------------------------+
| 6 |
+-----------------------------------------------------------------------------------------------------------+
To compute the count of elements in the union of multiple Bitmaps, including a NULL value:
select bitmap_or_count(bitmap_from_string('1,2,3'), bitmap_from_string('3,4,5'), to_bitmap(100), NULL);
The result will be:
+-------------------------------------------------------------------------------------------------+
| bitmap_or_count(bitmap_from_string('1,2,3'), bitmap_from_string('3,4,5'), to_bitmap(100), NULL) |
+-------------------------------------------------------------------------------------------------+
| NULL |
+-------------------------------------------------------------------------------------------------+