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select max的有关问题,如果表中无记录

发布时间: 2012-04-01 17:23:46 作者: rapoo

select max的问题,如果表中无记录能否让其返回1?
表结构:
song(id int, name vchar(50))
request(id int, songid, playseq, played)

SELECT song.id, MAX(requested.playseq) + 1 AS playseq
FROM song CROSS JOIN
request AS requested
WHERE (song.name = 'pclili ')
GROUP BY song.id

上面的语句在request里有记录时,可以成功执行,但若里面没有任何数据时,却查不到任何数据,能否让request里没有任何记录时也成功插入?

谢谢指点.在线等待!

[解决办法]
--try
isnull(MAX(requested.playseq),1)
[解决办法]
SELECT song.id, isnull(max(requested.playseq),0) + 1 AS playseq
FROM song CROSS JOIN
request AS requested
WHERE (song.name = 'pclili ')
GROUP BY song.id
[解决办法]
song(id int, name vchar(50))
request(id int, songid, playseq, played)

SELECT song.id, isnull(MAX(requested.playseq),1) + 1 AS playseq
FROM song CROSS JOIN
request AS requested
WHERE (song.name = 'pclili ')
GROUP BY song.id

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