bitmap_and

description

Syntax

BITMAP BITMAP_AND(BITMAP lhs, BITMAP rhs)

计算两个及以上输入bitmap的交集，返回新的bitmap.

example

  1. mysql> select bitmap_count(bitmap_and(to_bitmap(1), to_bitmap(2))) cnt;
  2. +------+
  3. | cnt  |
  4. +------+
  5. |    0 |
  6. +------+
  8. mysql> select bitmap_to_string(bitmap_and(to_bitmap(1), to_bitmap(2)));
  9. +----------------------------------------------------------+
  10. | bitmap_to_string(bitmap_and(to_bitmap(1), to_bitmap(2))) |
  11. +----------------------------------------------------------+
  12. |                                                          |
  13. +----------------------------------------------------------+
  15. mysql> select bitmap_count(bitmap_and(to_bitmap(1), to_bitmap(1))) cnt;
  16. +------+
  17. | cnt  |
  18. +------+
  19. |    1 |
  20. +------+
  22. MySQL> select bitmap_to_string(bitmap_and(to_bitmap(1), to_bitmap(1)));
  23. +----------------------------------------------------------+
  24. | bitmap_to_string(bitmap_and(to_bitmap(1), to_bitmap(1))) |
  25. +----------------------------------------------------------+
  26. | 1                                                        |
  27. +----------------------------------------------------------+
  29. MySQL> 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')));
  30. +-----------------------------------------------------------------------------------------------------------------------+
  31. | bitmap_to_string(bitmap_and(bitmap_from_string('1,2,3'), bitmap_from_string('1,2'), bitmap_from_string('1,2,3,4,5'))) |
  32. +-----------------------------------------------------------------------------------------------------------------------+
  33. | 1,2                                                                                                                   |
  34. +-----------------------------------------------------------------------------------------------------------------------+
  36. MySQL> 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()));
  37. +---------------------------------------------------------------------------------------------------------------------------------------+
  38. | 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())) |
  39. +---------------------------------------------------------------------------------------------------------------------------------------+
  40. |                                                                                                                                       |
  41. +---------------------------------------------------------------------------------------------------------------------------------------+
  43. MySQL> 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));
  44. +-----------------------------------------------------------------------------------------------------------------------------+
  45. | 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)) |
  46. +-----------------------------------------------------------------------------------------------------------------------------+
  47. | NULL                                                                                                                        |
  48. +-----------------------------------------------------------------------------------------------------------------------------+

keywords

  1. BITMAP_AND,BITMAP