substring_index

Name

SinceVersion 1.2

SUBSTRING_INDEX

description

Syntax

VARCHAR substring_index(VARCHAR content, VARCHAR delimiter, INT field)

Split content to two parts at position where the fields of delimiter stays, return one of them according to below rules: if field is positive, return the left part; else if field is negative, return the right part; if field is zero, return an empty string when content is not null, else will return null.

  • delimiter is case sensitive and multi-byte safe.
  • delimiter and field parameter should be constant.

example

  1. mysql> select substring_index("hello world", " ", 1);
  2. +----------------------------------------+
  3. | substring_index("hello world", " ", 1) |
  4. +----------------------------------------+
  5. | hello                                  |
  6. +----------------------------------------+
  7. mysql> select substring_index("hello world", " ", 2);
  8. +----------------------------------------+
  9. | substring_index("hello world", " ", 2) |
  10. +----------------------------------------+
  11. | hello world                            |
  12. +----------------------------------------+
  13. mysql> select substring_index("hello world", " ", -1);
  14. +-----------------------------------------+
  15. | substring_index("hello world", " ", -1) |
  16. +-----------------------------------------+
  17. | world                                   |
  18. +-----------------------------------------+
  19. mysql> select substring_index("hello world", " ", -2);
  20. +-----------------------------------------+
  21. | substring_index("hello world", " ", -2) |
  22. +-----------------------------------------+
  23. | hello world                             |
  24. +-----------------------------------------+
  25. mysql> select substring_index("hello world", " ", -3);
  26. +-----------------------------------------+
  27. | substring_index("hello world", " ", -3) |
  28. +-----------------------------------------+
  29. | hello world                             |
  30. +-----------------------------------------+
  31. mysql> select substring_index("hello world", " ", 0);
  32. +----------------------------------------+
  33. | substring_index("hello world", " ", 0) |
  34. +----------------------------------------+
  35. |                                        |
  36. +----------------------------------------+

keywords

  1. SUBSTRING_INDEX, SUBSTRING