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将结果从左连接转换为数组(或json或whatelse)

[英]Convert result from a left join to an array (or json or whatelse)

I actually have these tables : 我实际上有这些表:

- Table games -
ID
Name

- Table ean -
ID
ID_games
EAN

And I have this request : 我有这个要求:

SELECT games.*, ean.EAN
FROM games
LEFT JOIN ean ON (games.ID = ean.ID_games)

The result will be something like this : 结果将是这样的:

| 1 | Half Life | 358958595 |
| 1 | Half Life | 589584859 |
| 2 | Half Life 2 | 385953684 |
| 2 | Half Life 2 | 585100335 |
etc.

When I do my request and use it in php, it is not useful to have a lot of line with about the same results. 当我做我的请求并在php中使用它时,拥有大量具有相同结果的行是没有用的。 I would like to do something like this : 我想做这样的事情:

SELECT games.*, ConvertToArray(ean) AS ean_array
FROM games
LEFT JOIN ean ON (games.ID = ean.ID_games)

And have results like this : 并得到这样的结果:

| 1 | Half Life | (358958595,589584859) |
| 2 | Half Life 2 | (385953684,585100335 ) |
etc.

Is it possible to that with mysql ? 用mysql可以吗? Without an UDF ? 没有UDF? And with an UDF ? 用UDF?

Thank you, Kevin 谢谢你,凯文

Do you object to using GROUP_CONCAT ? 你反对使用GROUP_CONCAT吗? This would give you a nice delimited list (Assuming the ean value will never have your delimiter within): 这会给你一个很好的分隔列表(假设ean值永远不会有你的分隔符):

SELECT       games.*, GROUP_CONCAT(ean.EAN) AS ean_list,
FROM         games
  LEFT JOIN  ean
  ON         games.ID = ean.ID_games
GROUP BY     games.ID, games.name

Resulting in: 导致:

| 1 | Half Life   | 358958595,589584859 |
| 2 | Half Life 2 | 385953684,585100335 |

Also, here's a qeustion I found with this logic applied: mySql - creating a join using a list of comma separated values 此外,这是我在应用此逻辑时发现的qeustion: mySql - 使用逗号分隔值列表创建连接

See GROUP_CONCAT() . GROUP_CONCAT()

Example can be found here . 示例可以在这里找到。

Your query would look something like: 您的查询看起来像:

SELECT games.*, GROUP_CONCAT(DISTINCT ean) AS ean_array
FROM games
LEFT JOIN ean ON (games.ID = ean.ID_games)
GROUP BY games.ID

Try this one: 试试这个:

SELECT g.id, GROUP_CONCAT(CAST(e.ean AS CHAR) SEPARATOR ', ')
FROM games g
LEFT JOIN ean e ON g.id = e.id_games
GROUP BY g.id;

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