SQL按字符串排序奇怪的语法
是否有一种不那么丑陋/更具程序性的方法来解决这个问题:SQL按字符串排序奇怪的语法,sql,sql-server-2005,Sql,Sql Server 2005,是否有一种不那么丑陋/更具程序性的方法来解决这个问题: ORDER BY CASE WHEN lessonID = 'lesson_1' Then 1 WHEN lessonID = 'lesson_novid_1' Then 2 WHEN lessonID = 'lesson_2' Then 3 WHEN lessonID = 'lesson_novid_2' Then 4 WHEN lessonID = 'lesson_3' Then 5 WHEN lessonID
ORDER BY CASE
WHEN lessonID = 'lesson_1' Then 1
WHEN lessonID = 'lesson_novid_1' Then 2
WHEN lessonID = 'lesson_2' Then 3
WHEN lessonID = 'lesson_novid_2' Then 4
WHEN lessonID = 'lesson_3' Then 5
WHEN lessonID = 'lesson_novid_3' Then 6
WHEN lessonID = 'lesson_4' Then 7
WHEN lessonID = 'lesson_novid_4' Then 8
WHEN lessonID = 'lesson_5' Then 9
WHEN lessonID = 'lesson_novid_5' Then 10
WHEN lessonID = 'lesson_6' Then 11
WHEN lessonID = 'lesson_novid_6' Then 12
WHEN lessonID = 'lesson_7' Then 13
WHEN lessonID = 'lesson_novid_7' Then 14
WHEN lessonID = 'lesson_8' Then 15
WHEN lessonID = 'lesson_novid_8' Then 16
WHEN lessonID = 'lesson_9' Then 17
WHEN lessonID = 'lesson_novid_9' Then 18
WHEN lessonID = 'lesson_10' Then 19
WHEN lessonID = 'lesson_novid_10' Then 20
WHEN lessonID = 'lesson_11' Then 21
WHEN lessonID = 'lesson_novid_11' Then 22
WHEN lessonID = 'lesson_12' Then 23
WHEN lessonID = 'lesson_novid_12' Then 24
End ASC
不,这就是你必须要做的,但我使用了一种稍微不同的(更干净?)语法: 但这几乎是一样的。遗憾的是,您无法使用变量/参数进行排序,因为您可能已经发现了这一点
ORDER BY @parameter DESC
也许MS会在未来的版本中将其放入=)创建一个包含lessonId和sortPosition列的表。加入到那个里,按排序位置排序 尝试查找数字并将其转换为整数:
ORDER BY
CAST(REPLACE(REPLACE(lessonID, 'lesson_', ''), 'novid_', '') AS INT),
lessonID
在线查看它的工作情况:
请注意,此查询将无法使用索引执行排序。您可以考虑使用A和索引来提高性能。
将所有的选择堆叠到子字符串位置上的分隔字符串和顺序:
order by CharIndex( '|' + lessonID + '|', '|lesson_1|lesson_novid_1|...|' )
就个人而言,我更喜欢WW使用查找表的答案
order by CharIndex( '|' + lessonID + '|', '|lesson_1|lesson_novid_1|...|' )