bitmap_from_string

description

Syntax

BITMAP BITMAP_FROM_STRING(VARCHAR input)

将一个字符串转化为一个BITMAP，字符串是由逗号分隔的一组unsigned bigint数字组成.(数字取值在:0 ~ 18446744073709551615) 比如”0, 1, 2”字符串会转化为一个Bitmap，其中的第0, 1, 2位被设置. 当输入字段不合法时，返回NULL

example

1. mysql> select bitmap_to_string(bitmap_empty());
2. +----------------------------------+
3. | bitmap_to_string(bitmap_empty()) |
4. +----------------------------------+
5. |                                  |
6. +----------------------------------+

8. mysql> select bitmap_to_string(bitmap_from_string("0, 1, 2"));
9. +-------------------------------------------------+
10. | bitmap_to_string(bitmap_from_string('0, 1, 2')) |
11. +-------------------------------------------------+
12. | 0,1,2                                           |
13. +-------------------------------------------------+

15. mysql> select bitmap_from_string("-1, 0, 1, 2");
16. +-----------------------------------+
17. | bitmap_from_string('-1, 0, 1, 2') |
18. +-----------------------------------+
19. | NULL                              |
20. +-----------------------------------+

23. mysql> select bitmap_to_string(bitmap_from_string("0, 1, 18446744073709551615"));
24. +--------------------------------------------------------------------+
25. | bitmap_to_string(bitmap_from_string('0, 1, 18446744073709551615')) |
26. +--------------------------------------------------------------------+
27. | 0,1,18446744073709551615                                           |
28. +--------------------------------------------------------------------+

keywords

1. BITMAP_FROM_STRING,BITMAP