--drop table t
create table t(c1 int,c2 int)insert into t
select 1,100 union all
select 1,200 union all
select 2,100 union all
select 2,200 union all
select 2,300 union all
select 3,50 union all
select 3,200 union all
select 4,50 union all
select 4,200 union all
select 4,300

select c1 from t
group by c1
having min(c2)>=100 and count(1)=3

--drop table t_orderby
create table t_orderby
(
c1 int null,
c2 varchar(10) null,
c3 varchar(10) null
)insert into t_orderby
select 1,'2','a1' union all
select 1,'1','a2' union all
select 3,'1','ab' union all
select 1,'4','b1'

select * from t_orderby
where c2='4'
union all
select * from t_orderby
where c2='1'
union all
select * from t_orderby
where c2='2'

select * from t_orderby
order by charindex(c2,'4,1,2') 

select * from t_orderby
order by case
         when c2='4' then 1
         when c2='1' then 2
         when c2='2' then 3
         end,c1 desc

select * from t_orderby
order by case
         when c2='4' then 1
         else 1+rand()
         end

select * from t_orderby
order by newid()

select top 1 * from t_orderby
order by newid()

select * from t_orderby
order by left(c3,1),ASCII(substring(c3,2,1))

--drop table t_count
create table t_count
(
c1 varchar(10) null,
c2 varchar(10) null
)insert into t_count values(null,null)
insert into t_count values('a','b')
insert into t_count values('a','b')
insert into t_count values('c','d')

select COUNT(c1) from t_count --3
select COUNT(distinct c1) from t_count --2

select COUNT(*) from t_count --4
select COUNT(1) from t_count --4
select COUNT(1000) from t_count --4

--正常
select count(*) from (select c1,c2 from t_count group by c1,c2) t --3
select count(*) from (select distinct c1,c2 from t_count) t --3
--有NULL参与了运算，所以表达式值为NULL
select count(distinct c1+c2) from t_count --2

--drop table t1,t2
create table t1
(
url        varchar(1000)
)create table t2
(
code        varchar(1000)
)--insert
insert into t1
select 'http://www.baidu.com/test1' union all
select 'http://www.baidu.com/test2' union all
select 'http://www.baidu.com/test3' union all
select 'www.baidu.com/test1' union all
select 'www.baidu.com/test2' union all
select 'http://www.google.com/test1' union all
select 'http://www.google.com/test2' union all
select 'http://www.sogou.com/test3' union all
select 'http://www.sogou.com/test4'insert into t2
select 'baidu.com' union all
select 'sogou.com'

select t2.code,t1.url from t1
inner join t2
on CHARINDEX(t2.code,t1.url) > 0--结果如下
/*
baidu.com    http://www.baidu.com/test1
baidu.com    http://www.baidu.com/test2
baidu.com    http://www.baidu.com/test3
baidu.com    www.baidu.com/test1
baidu.com    www.baidu.com/test2
sogou.com    http://www.sogou.com/test3
sogou.com    http://www.sogou.com/test4
*/