我运行了条SQL语句,返回了记录,不太明白,请大家指点select * from (
select 'abc' as d) as a where d between 'a' and 'b'按我的理解,不应该有返回记录值才对呀,请大家讲讲原理
谢谢
select 'abc' as d) as a where d between 'a' and 'b'按我的理解,不应该有返回记录值才对呀,请大家讲讲原理
谢谢
调试欢乐多
select 'abc' as d) as a where d between 'a' and 'b' 有啥问题不?'ABC'是BETWEEN 'A'
SELECT ASCII('ABC')
SELECT ASCII('A')
-----------
65(所影响的行数为 1 行)
-----------
65(所影响的行数为 1 行)
select *
from (select 'abc' as d) as a
where d between 'a' and 'b'(select 'abc' as d) as a 产生一个一条记录的结果集。其字段名为 d, 值为 'abc'select *
from xxx
where d between 'a' and 'b'
'a'<'abc' <'b'
/*d
----
abc(1 行受影响)*/
a
abc
b
大小顺序是这样的
select 'abc' as d) as a where d between 'a' and 'ab'select * from (
select 'abc' as d) as a where d between 'a' and 'abb'
print 'yes'
else
print 'no'/*yes*/
ABC和AB
先比较AB,都一样,再比较空和C,空小,所以
ABC>AB
下面则是比较
C和B,所以ABC>ABB