求一条sqlserver查询语句

Question

我有一个表totalmodel,里面有一个字段NuitNo,该字段里面的内容有2中形式，YR***,YK***.假设现在有YR123,YRasdf,YR12,YKwed,YK,YKdfg.我现在想通过分组查询得到YK,和YK.这两个大类，即得到的记录条数为2条，请问该怎么办呢？

Answer 1

select
   left(NuitNo,2),count(1) as num
from
    totalmodel
group by
   left(NuitNo,2)

Answer 2

select typecode=left(NuitNo,2),cunt(1)
from tb
group by left(NuitNo,2)

Answer 3

或
select
   substring(NuitNo,1,2),count(1) as num
from
    totalmodel
group by
      substring(NuitNo,1,2)

Answer 4

select distinct left(NuitNo,2) from totalmodel

Answer 5

select
   left(NuitNo,2),count(1) as num
from
    totalmodel
group by
   left(NuitNo,2)

Answer 6

select substring(NuitNo,1,2) from totalmodel group by substring(NuitNo,1,2)

Answer 7

select subString(NuitNo,1,2) 形式 ,count(NuitNo)记录数 from totalmodel 
group by subString(NuitNo,1,2)

Answer 8

select
   substring(NuitNo,1,2) type_name,count(1) as type_num
from
    totalmodel
group by
      substring(NuitNo,1,2)