| --- |
| { |
| "title": "SUBSTRING_INDEX", |
| "language": "en" |
| } |
| --- |
| |
| ## substring_index |
| |
| ### Name |
| |
| <version since="1.2"> |
| |
| SUBSTRING_INDEX |
| |
| </version> |
| |
| ### description |
| |
| #### Syntax |
| |
| `VARCHAR substring_index(VARCHAR content, VARCHAR delimiter, INT field)` |
| |
| Split `content` to two parts at position where the `field`s 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 |
| |
| ``` |
| mysql> select substring_index("hello world", " ", 1); |
| +----------------------------------------+ |
| | substring_index("hello world", " ", 1) | |
| +----------------------------------------+ |
| | hello | |
| +----------------------------------------+ |
| mysql> select substring_index("hello world", " ", 2); |
| +----------------------------------------+ |
| | substring_index("hello world", " ", 2) | |
| +----------------------------------------+ |
| | hello world | |
| +----------------------------------------+ |
| mysql> select substring_index("hello world", " ", -1); |
| +-----------------------------------------+ |
| | substring_index("hello world", " ", -1) | |
| +-----------------------------------------+ |
| | world | |
| +-----------------------------------------+ |
| mysql> select substring_index("hello world", " ", -2); |
| +-----------------------------------------+ |
| | substring_index("hello world", " ", -2) | |
| +-----------------------------------------+ |
| | hello world | |
| +-----------------------------------------+ |
| mysql> select substring_index("hello world", " ", -3); |
| +-----------------------------------------+ |
| | substring_index("hello world", " ", -3) | |
| +-----------------------------------------+ |
| | hello world | |
| +-----------------------------------------+ |
| mysql> select substring_index("hello world", " ", 0); |
| +----------------------------------------+ |
| | substring_index("hello world", " ", 0) | |
| +----------------------------------------+ |
| | | |
| +----------------------------------------+ |
| ``` |
| ### keywords |
| |
| SUBSTRING_INDEX, SUBSTRING |