大Mysql查询（联接计入结果并修改字符串）

Question

I am brand new to mysql so please excuse my level of knowledge here, and feel free to direct me in a better direction if what I am doing is out of date.

I am pulling information from a database to fill in a php page.

My tables:

Server:

|ServerID (int) | ArticleID (int) | locationID (int) |
|   1           |       46        | 55               |
|   2           |       11        | 81               |
|   3           |       81        | 46               |
|   4           |       55        | 11               |
|   5           |       81        | 99               |
|   5           |       11        | 52               |

Article:

|ArticleID (int)  | Name (varchar)  | Typ (int) |
|   46            |   domain        | 0         |
|   81            |   root-server   | 1         |
|   55            |   vserver       | 2         |
|   11            |   root-server2  | 1         |

Location:

|LocationID (int) | location (varchar) | 
|   46            | 1-5-15-2           |
|   81            | 1-5-14-2           |
|   55            | 2-25-1-9           |
|   11            | 21-2-5-8           |
|   99            | 17-2-5-8           |
|   52            | 1-8-5-8            |

Result:

|location (int) | name (varchar) | count (int) |
| 1             | root-server    | 1           |
| 1             | root-server2   | 2           |
| 17            | root-server    | 1           |

The location in the result is the first number block of the location in the location table (1-5-15-2 -> 1, 1-8-5-8 -> 1, 21-2-5-8 -> 21, 17-2-5-8 -> 17). The count is the sum of all servers with the same name and the same first location block.

Do anyone think its possible to get this result in only one query?

Thanks for any answer!

Answer 1

Please give this a shot:

SELECT 
    s.locationID as id, a.name, count(*) as count
FROM
    `Server` s
    LEFT JOIN
    `Article` a ON s.ArticleID = a.ArticleID
GROUP BY s.locationID, a.name

Answer 2

something like this should work

select 
    s.location_id as location, a.name, count(location) as count 
from 
    server as s, article as a 
where 
    s.articleID = a.articleID 
group by location, a.name

Answer 3

Check this

SELECT  SUBSTRING_INDEX(location, '-', 1) as LID,Article.Name,Count(*) as Count 
from Location join Server  
on Server.locationID=Location.locationID  
join Article on Article.ArticleID=Server.ArticleID
group by LID,Article.ArticleID  ;

DEMO