Getting a list of unique values from a MySQL column



mysql> select * from train;

+-------+--------+-------------+-----+

| time  | length | destination | tid |

+-------+--------+-------------+-----+

| 07:05 |      1 | Salisbury   |   1 |

| 08:18 |      2 | Swindon     |   2 |

| 09:05 |      2 | Southampton |   3 |

| 05:45 |      1 | Swindon     |   4 |

| 10:35 |     12 | Plymouth    |  10 |

| 13:49 |      2 | Swindon     |   6 |

| 14:20 |      2 | Salisbury   |   7 |

| 17:07 |      1 | Swindon     |   8 |

| 18:18 |      1 | Salisbury   |   9 |

| 13:00 |      6 | Windsor     |  11 |

+-------+--------+-------------+-----+

10 rows in set (0.04 sec)



mysql> select distinct destination from train;

+-------------+

| destination |

+-------------+

| Salisbury   |

| Swindon     |

| Southampton |

| Plymouth    |

| Windsor     |

+-------------+

5 rows in set (0.08 sec)



mysql>

See More on SQL module.

(written 2005-04-14, updated 2006-06-05)

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Comment: "Havent seen your site crop up in sql searches for years. I ..." Visitor Ranking 4.0 (5=excellent, 1=poor)

Comment by Colin (published 2010-10-08) Suggested link.
Havent seen your site crop up in sql searches for years. I this page found searching for a solution to a slightly different problem:
I need a list of unique values AND an id. Any id will do. First or last.
So how from your table: How to return the distinct destination along with a `tid` Pick a tid, any tid?

stackoverflow has a similar prob. I give link. My col I want unique has some heavy calcs so am trying to avoid multi selects and joins as far as poss. [#3783]

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