tsql - Creating a view with a column not in the base table -


i have table 4 columns. being asked create view performs calculation , puts results in column not in table.

here is: create view called v_count shows number of students working on each assignment. view should have columns assignment number , count.

the underlying table not have count column.

well have make use of count function , group by clause. suppose have student id , assignment id in table:

sid asnid 1   1 1   2 2   1 2   5 2   8 3   2 3   4

then following query give count of students working on assignments: 

select asnid [assignment], count(sid) [students]  assignment  group asnid

now can use query create view. read docs count , group by


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