bitmap_xor

description

Syntax

BITMAP BITMAP_XOR(BITMAP lhs, BITMAP rhs, ...)

计算两个及以上输入bitmap的差集，返回新的bitmap.

example

  1. mysql> select bitmap_count(bitmap_xor(bitmap_from_string('2,3'),bitmap_from_string('1,2,3,4'))) cnt;
  2. +------+
  3. | cnt  |
  4. +------+
  5. |    2 |
  6. +------+
  8. mysql> select bitmap_to_string(bitmap_xor(bitmap_from_string('2,3'),bitmap_from_string('1,2,3,4')));
  9. +----------------------------------------------------------------------------------------+
  10. | bitmap_to_string(bitmap_xor(bitmap_from_string('2,3'), bitmap_from_string('1,2,3,4'))) |
  11. +----------------------------------------------------------------------------------------+
  12. | 1,4                                                                                    |
  13. +----------------------------------------------------------------------------------------+
  15. MySQL> select bitmap_to_string(bitmap_xor(bitmap_from_string('2,3'),bitmap_from_string('1,2,3,4'),bitmap_from_string('3,4,5')));
  16. +---------------------------------------------------------------------------------------------------------------------+
  17. | bitmap_to_string(bitmap_xor(bitmap_from_string('2,3'), bitmap_from_string('1,2,3,4'), bitmap_from_string('3,4,5'))) |
  18. +---------------------------------------------------------------------------------------------------------------------+
  19. | 1,3,5                                                                                                               |
  20. +---------------------------------------------------------------------------------------------------------------------+
  22. MySQL> select bitmap_to_string(bitmap_xor(bitmap_from_string('2,3'),bitmap_from_string('1,2,3,4'),bitmap_from_string('3,4,5'),bitmap_empty()));
  23. +-------------------------------------------------------------------------------------------------------------------------------------+
  24. | bitmap_to_string(bitmap_xor(bitmap_from_string('2,3'), bitmap_from_string('1,2,3,4'), bitmap_from_string('3,4,5'), bitmap_empty())) |
  25. +-------------------------------------------------------------------------------------------------------------------------------------+
  26. | 1,3,5                                                                                                                               |
  27. +-------------------------------------------------------------------------------------------------------------------------------------+
  29. MySQL> select bitmap_to_string(bitmap_xor(bitmap_from_string('2,3'),bitmap_from_string('1,2,3,4'),bitmap_from_string('3,4,5'),NULL));
  30. +---------------------------------------------------------------------------------------------------------------------------+
  31. | bitmap_to_string(bitmap_xor(bitmap_from_string('2,3'), bitmap_from_string('1,2,3,4'), bitmap_from_string('3,4,5'), NULL)) |
  32. +---------------------------------------------------------------------------------------------------------------------------+
  33. | NULL                                                                                                                      |
  34. +---------------------------------------------------------------------------------------------------------------------------+

keyword

  1. BITMAP_XOR,BITMAP