求如何动态隐藏列为空的SQL语句

[medical52001]

想问下 比如 select ID,a1,a2,a3,a4,a5 from temp_test
然后返回一些记录，
ID a1 a2 a3 a4 a5
1001 32 34 35
1002 23 34 35
1003 20 31 33
然后我想实现的效果是，如果列为空，就不显示该列，有数据就显示
就象a1无数值，就不显示
ID a2 a3 a4 a5
1001 32 34 35
1002 23 34 35
1003 20 31 33


请问这个用SQL语句如何实现？？？？

[you_tube]

在代码里控制吧
SQL里很难做到

[csdyyr]

CREATE TABLE TB(ID VARCHAR(4),    a1  INT,  a2 INT, a3 INT, a4 INT, a5 INT)
INSERT TB
SELECT '1001',  NULL, 32,  NULL, 34,  35 UNION ALL 
SELECT '1002',  NULL, NULL, 23,  34,  35 UNION ALL 
SELECT '1003',  NULL, 20,  31, NULL,  33

DECLARE @STR VARCHAR(8000)
SET @STR=''
SELECT @STR= 
	ISNULL((SELECT TOP 1 'A1' FROM TB WHERE A1 IS NOT NULL), '')+','+
	ISNULL((SELECT TOP 1 'A2' FROM TB WHERE A2 IS NOT NULL), '')+','+
	ISNULL((SELECT TOP 1 'A3' FROM TB WHERE A3 IS NOT NULL), '')+','+
	ISNULL((SELECT TOP 1 'A4' FROM TB WHERE A4 IS NOT NULL), '')+','+
	ISNULL((SELECT TOP 1 'A5' FROM TB WHERE A5 IS NOT NULL), '')

EXEC('SELECT ID'+@STR+' FROM TB')

DROP TABLE TB
/*
ID   A2          A3          A4          A5
---- ----------- ----------- ----------- -----------
1001 32          NULL        34          35
1002 NULL        23          34          35
1003 20          31          NULL        33
*/

[chenjf029]

好bbbbbbbb