How can I get the count in SQL?

How can I count unique items in sql?

• I got help from here: for a query and from that I got this query: SELECT userID, COUNT(beerName) as NumberofBeers FROM uniqueBeers WHERE userID IN (3, 6) GROUP BY userID ORDER BY `uniqueBeers`.`userID` ASC this returns me a user id with how many beers they have in the database. Each row in this table is a beer and each beer by user is unique so I was able to get a count of unique beers by user. What I am trying to do now is, count unique breweries for each user. Unlike the last query where a user does not have doubles for a beer. They can for a brewery. I am lost on how to create a query that will count unique breweries for each user. Thanks!

• Answer:

  SQL supports the DISTINCT keyword inside some aggregate functions. SELECT userID, COUNT(DISTINCT beerName) AS NumberOfDistinctBeers FROM uniqueBeers WHERE userID IN (3, 6) GROUP BY userID ORDER BY userID ASC The meaning is that it only counts each distinct value once within each group.  Without the DISTINCT, it will count every row where the expression is not NULL.