Question

Here is what I have:

A MSSQL DB and table with lets say 200 rows

Python 2.7 and pyodbc

There is a column, we will call type, and in the rows under it contain an unknown quantity of unique values. For instance, right now there is the possibility of a,b,c,d,e and f for the values but in the future, a may go away or we might add g.

Therefore I do not believe I can have a predefined set of variables or a dictionary of some sorts to reference.

My goal is to have python/sql look at the table, determine how many unique items there are and then count up the totals of each unique item, giving me an output like: there are 50 a’s and 23 b’s and 5 c’s

Is there some function out there that accomplishes this or is there something in SQL that would do this for me? Would I have to determine the amount of unique items and then run sql statements for each item?

Answer 1

You probably just want the count function:

COUNT

Returns the number of items in a group.

select count(*), type from that_one_table group by type

The MSDN reference for group by describes it better than I could:

GROUP BY

Groups a selected set of rows into a set of summary rows by the values of one or more columns or expressions in SQL Server 2012. One row is returned for each group. Aggregate functions in the SELECT clause list provide information about each group instead of individual rows.