简体   繁体   中英

SQL SELECT - group multiple values on a single row

I have a table with the following data:

ID  CAT  TYPE   SUBPRODUCT
--- ---- ------ ----------------
1   1     1       AA
2   1     1       BB
3   1     2       CC

I'd like to get the data like this:

CAT   TYPE   SUBPRODUCT
----- ------ ---------------
1     1      AA,BB
1     2      CC

pls reply me what should i do.

Thanks.

You can use FOR XML PATH . While a bit hard to read, afaik it currently is the most concise way to concatenate strings.

Breakdown

  • FOR XML PATH concatenates all values that match the subselect
  • STUFF removes the leading comma

SQL Statement

SELECT  q.CAT
        , q.TYPE
        , SUBPRODUCT = STUFF((SELECT ', ' + qi.SUBPRODUCT FROM q qi WHERE qi.Cat = q.Cat AND qi.Type = q.Type FOR XML PATH('')), 1, 2, '')
FROM    q
GROUP BY
        q.CAT
        , q.TYPE

Test script

;WITH q AS (
  SELECT * FROM (VALUES 
    (1, 1, 1, 'AA')
    , (2, 1, 1, 'BB')
    , (3, 1, 2, 'CC')
  ) AS a (ID, CAT, TYPE, SUBPRODUCT)    
)
SELECT  q.CAT
        , q.TYPE
        , SUBPRODUCT = STUFF((SELECT ', ' + qi.SUBPRODUCT FROM q qi WHERE qi.Cat = q.Cat AND qi.Type = q.Type FOR XML PATH('')), 1, 2, '')
FROM    q
GROUP BY
        q.CAT
        , q.TYPE

The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.

 
粤ICP备18138465号  © 2020-2024 STACKOOM.COM