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標題: Generating Log Code (Surrogate Key) [打印本頁]

作者: luckiejacky 時間: 2013-10-17 10:11 標題: Generating Log Code (Surrogate Key)

String str1 = "select 'LOG' || replace(substr(quote(zeroblob((9 + 1) / 2)), 3, (9 - length('LOG') - length(max(IFNULL(e.LogID,0)+1)))), ''', '') || "
+" max(IFNULL(e.LogID,0)+1) || '-' || strftime('%Y-%m-%d', date('now'))"
+" from elog e ";

複製代碼

What happens when there are no rows in the
database initially.
Thanks

作者: henrywho 時間: 2013-10-17 11:15

Why dun you try 1st?

And some times, for related reasons, we need to use nested ifnull() / nvl()

作者: luckiejacky 時間: 2013-10-17 14:54

Thanks, I have solved it by Java instead