一个between A and B 问题!!!!(50分)

  • 主题发起人 zhang12321
  • 开始时间
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zhang12321

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GUEST, unregistred user!
对于给定的条件A&B
不管是A>B还是A<B
我都想查在A和B之间的数据
如between 4 and 6或between 6 and 4之间的
我该如何写SQL呢?
要写成
and
..........
and (X between A and B or X betwwen B and A)吗???

 
(field>a and field<b)or(field<a and field>b)
 
if a<b then
SQL_String:=SQL_String+‘and (X between A and B)’;
else
if a>b then
SQL_String:=SQL_String+‘and (X between B and A)’;
 
ugvanxk,
你说是要这么写吗:
select * from XXX where
task_a=1 and task_b=2 ........and ((task_c>a and task_c<b)or(task_c<a and task_c>b))
谢谢!!!
 
还有更好的方法吗???
 
----between a and b
a must less then b
it's equal ' a<= value <= b '
if a larger then b, condition always false & no use to select
 
if a>b then
between b and a
else
between a and b
 
如果你使用的是Access数据库,那么
X between A and B 和 X betwwen B and A的结果是一样的,不管A>B 还是A<B

 
想问问我怎么样产生一个顺序的序列,但是不要空缺后面的数据?
例如,1,2,3,4,6,7,8,9
我要产生的结果是1,2,3,4,就是说最后一个是4
vb里面用between ? and ?就可以了,不知道delphi怎么样?
 
第一种,最直接的形式:
SQL
select * from table1 a
where a.a1 between A and B
第二中,变量:
select * from table1 a
where a.a1 between :n1 and :n2
在DELPHI 的param 属性中设置n1,n2 的类型。然后赋值
 
最好在外面判断再传进去!
 
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