sqlserver 竖表转横表

CREATE TABLE t(name VARCHAR(10), object VARCHAR(10), score INT)
INSERT t SELECT 'a',      'EN'  ,   89
UNION ALL SELECT 'a',     'CH'  ,   78
UNION ALL SELECT 'a' ,    'HO'  ,   99
UNION ALL SELECT 'b'  ,   'EN'  ,   34
UNION ALL SELECT 'b'   ,  'CH'  ,   88
UNION ALL SELECT 'b'    , 'HO'  ,   66

--object出现的不同值的个数是有限的那么使用
SELECT name,
 EN=MAX(CASE WHEN object='EN' THEN score ELSE 0 END),
 CH=MAX(CASE WHEN object='CH' THEN score ELSE 0 END),
 HO=MAX(CASE WHEN object='HO' THEN score ELSE 0 END)
FROM t
GROUP BY name

--若object出现的不同值是不定的
DECLARE @sql VARCHAR(8000)
SET @sql='SELECT name'
SELECT @sql=@sql+',['+object+']=MAX(CASE object WHEN '''+object+''' THEN score ELSE 0 END)' FROM t GROUP BY object
EXEC(@sql+' FROM t GROUP BY name')

DROP TABLE t