Is it possible to specify a condition in Count()? I would like to count only the rows that have, for example, "Manager" in the Position column.
I want to do it in the count statement, not using WHERE; I'm asking about it because I need to count both Managers and Other in the same SELECT (something like Count(Position = Manager), Count(Position = Other)) so WHERE is no use for me in this example.
Best Answer
If you can't just limit the query itself with a where clause, you can use the fact that the count aggregate only counts the non-null values:
select count(case Position when 'Manager' then 1 else null end)from ...You can also use the sum aggregate in a similar way:
select sum(case Position when 'Manager' then 1 else 0 end)from ...Assuming you do not want to restrict the rows that are returned because you are aggregating other values as well, you can do it like this:
select count(case when Position = 'Manager' then 1 else null end) as ManagerCountfrom ...Let's say within the same column you had values of Manager, Supervisor, and Team Lead, you could get the counts of each like this:
select count(case when Position = 'Manager' then 1 else null end) as ManagerCount,count(case when Position = 'Supervisor' then 1 else null end) as SupervisorCount,count(case when Position = 'Team Lead' then 1 else null end) as TeamLeadCount,from ...@Guffa 's answer is excellent, just point out that maybe is cleaner with an IF statement
select count(IIF(Position = 'Manager', 1, NULL)) as ManagerCountfrom ...Depends what you mean, but the other interpretation of the meaning is where you want to count rows with a certain value, but don't want to restrict the SELECT to JUST those rows...
You'd do it using SUM() with a clause in, like this instead of using COUNT():e.g.
SELECT SUM(CASE WHEN Position = 'Manager' THEN 1 ELSE 0 END) AS ManagerCount,SUM(CASE WHEN Position = 'CEO' THEN 1 ELSE 0 END) AS CEOCountFROM SomeTableIf using Postgres or SQLite, you can use the Filter clause to improve readability:
SELECTCOUNT(1) FILTER (WHERE POSITION = 'Manager') AS ManagerCount,COUNT(1) FILTER (WHERE POSITION = 'Other') AS OtherCountFROM ...BigQuery also has Countif - see the support across different SQL dialects for these features here:https://modern-sql.com/feature/filter
You can also use the Pivot Keyword if you are using SQL 2005 or above
more info and from Technet
SELECT *FROM @UsersPIVOT (COUNT(Position)FOR PositionIN (Manager, CEO, Employee)) as pTest Data Set
DECLARE @Users TABLE (Position VARCHAR(10))INSERT INTO @Users (Position) VALUES('Manager')INSERT INTO @Users (Position) VALUES('Manager')INSERT INTO @Users (Position) VALUES('Manager')INSERT INTO @Users (Position) VALUES('CEO')INSERT INTO @Users (Position) VALUES('Employee')INSERT INTO @Users (Position) VALUES('Employee')INSERT INTO @Users (Position) VALUES('Employee')INSERT INTO @Users (Position) VALUES('Employee')INSERT INTO @Users (Position) VALUES('Employee')INSERT INTO @Users (Position) VALUES('Employee')Do you mean just this:
SELECT Count(*) FROM YourTable WHERE Position = 'Manager'If so, then yup that works!
I know this is really old, but I like the NULLIF trick for such scenarios, and I found no downsides so far. Just see my copy&pasteable example, which is not very practical though, but demonstrates how to use it.
NULLIF might give you a small negative impact on performance, but I guess it should still be faster than subqueries.
DECLARE @tbl TABLE ( id [int] NOT NULL, field [varchar](50) NOT NULL)INSERT INTO @tbl (id, field)SELECT 1, 'Manager'UNION SELECT 2, 'Manager'UNION SELECT 3, 'Customer'UNION SELECT 4, 'Boss'UNION SELECT 5, 'Intern'UNION SELECT 6, 'Customer'UNION SELECT 7, 'Customer'UNION SELECT 8, 'Wife'UNION SELECT 9, 'Son'SELECT * FROM @tblSELECT COUNT(1) AS [total],COUNT(1) - COUNT(NULLIF([field], 'Manager')) AS [Managers],COUNT(NULLIF([field], 'Manager')) AS [NotManagers],(COUNT(1) - COUNT(NULLIF([field], 'Wife'))) + (COUNT(1) - COUNT(NULLIF([field], 'Son'))) AS [Family]FROM @tblComments appreciated :-)
Here is what I did to get a data set that included both the total and the number that met the criteria, within each shipping container. That let me answer the question "How many shipping containers have more than X% items over size 51"
selectSchedule,PackageNum,COUNT (UniqueID) as Total,SUM (casewhenSize > 51 then1 else0 end) as NumOverSize fromInventory wherecustomer like '%PEPSI%' group bySchedule, PackageNumNote with PrestoDB SQL (from Facebook), there is a shortcut:
https://prestodb.io/docs/current/functions/aggregate.html
count_if(x) → bigint
Returns the number of TRUE input values. Thisfunction is equivalent to count(CASE WHEN x THEN 1 END)
In MySQL, boolean expressions evaluate to 0 or 1, so the following aggregation works:
select sum(Position = 'Manager') as ManagerCountfrom ...SELECT COUNT(*) FROM bla WHERE Position = 'Manager'I think you can use a simple WHERE clause to select only the count some record.