BITMAP_AND
描述
计算两个及以上输入的 BITMAP 的交集,返回新的 BITMAP.
语法
BITMAP_AND(<bitmap>, <bitmap>,[, <bitmap>...])参数
| 参数 | 说明 |
|---|---|
<bitmap> | 被求交集的原 BITMAP 之一 |
返回值
返回一个 BITMAP
- 当参数存在空值时,返回 NULL
举例
select bitmap_to_string(bitmap_and(bitmap_from_string('1,2,3'), bitmap_from_string('1,2'), bitmap_from_string('1,2,3,4,5')));+-----------------------------------------------------------------------------------------------------------------------+
| bitmap_to_string(bitmap_and(bitmap_from_string('1,2,3'), bitmap_from_string('1,2'), bitmap_from_string('1,2,3,4,5'))) |
+-----------------------------------------------------------------------------------------------------------------------+
| 1,2 |
+-----------------------------------------------------------------------------------------------------------------------+select bitmap_to_string(bitmap_and(bitmap_from_string('1,2,3'), bitmap_from_string('1,2'), bitmap_from_string('1,2,3,4,5'),bitmap_empty()));+---------------------------------------------------------------------------------------------------------------------------------------+
| bitmap_to_string(bitmap_and(bitmap_from_string('1,2,3'), bitmap_from_string('1,2'), bitmap_from_string('1,2,3,4,5'), bitmap_empty())) |
+---------------------------------------------------------------------------------------------------------------------------------------+
| |
+---------------------------------------------------------------------------------------------------------------------------------------+select bitmap_to_string(bitmap_and(bitmap_from_string('1,2,3'), bitmap_from_string('1,2'), bitmap_from_string('1,2,3,4,5'),NULL));+-----------------------------------------------------------------------------------------------------------------------------+
| bitmap_to_string(bitmap_and(bitmap_from_string('1,2,3'), bitmap_from_string('1,2'), bitmap_from_string('1,2,3,4,5'), NULL)) |
+-----------------------------------------------------------------------------------------------------------------------------+
| NULL |
+-----------------------------------------------------------------------------------------------------------------------------+