Question

I have a table which has a recurring field. I need a function to count and say which recurrence is in nth line. i.e.;

If the table is as follows;

ID  NAME  CLASS
---------------
 1  Tom    a
 2  Dick   b
 3  Harry  c  
 4  Marry  b
 5  Bob    c
 6  Mat    c
 7  Mandi  a

A function like COUNT(class) can count how many times each class value has been occurred. But I need a function to output a result like follows;

ID  NAME  CLASS (I_NEED) COUNT
--------------------------------
 1  Tom     a      1       2
 2  Dick    b      1       2
 3  Harry   c      1       3
 4  Marry   b      2       2
 5  Bob     c      2       3
 6  Mat     c      3       3
 7  Mandi   a      2       2

I am using SQL Server 2010R2

Any ideas will come in great help.. Thanks in advance!!

Answer 1

I think this is what you are looking for:

select id, 
       name, 
       class,
       row_number() over (partition by class order by id) as i_need,
       count(*) over (partition by class) as cnt
from the_table
order by id