跳到主要内容

BITMAP_NOT

bitmap_not

description

Syntax

BITMAP BITMAP_NOT(BITMAP lhs, BITMAP rhs)

计算lhs减去rhs之后的集合,返回新的bitmap.

example

mysql> select bitmap_to_string(bitmap_not(bitmap_from_string('2,3'),bitmap_from_string('1,2,3,4')));
+----------------------------------------------------------------------------------------+
| bitmap_to_string(bitmap_not(bitmap_from_string('2,3'), bitmap_from_string('1,2,3,4'))) |
+----------------------------------------------------------------------------------------+
| |
+----------------------------------------------------------------------------------------+
1 row in set (0.01 sec)

mysql> select bitmap_to_string(bitmap_not(bitmap_from_string('2,3,5'),bitmap_from_string('1,2,3,4')));
+----------------------------------------------------------------------------------------+
| bitmap_to_string(bitmap_not(bitmap_from_string('2,3,5'), bitmap_from_string('1,2,3,4'))) |
+----------------------------------------------------------------------------------------+
| 5 |
+----------------------------------------------------------------------------------------+

keywords

BITMAP_NOT,BITMAP