![]() ![]() I also included this SQL - which lets you easily count (manually) the number of UNIQUE entries. ROW_NUMBER() OVER (PARTITION BY status_to ORDER BY status_to) AS rn This query demonstrates how you can easily pick out those DISINCT values of status_to that have more than one record: SELECT COUNT(rn) OVER (PARTITION BY rn) AS "Unique count" Notice the extreme difference in the results of EXPLAIN ANALYZE at the bottom of the fiddle for this new query and my old one! ADD CONSTRAINT PKPerson PRIMARY KEY (ID,LastName) Note: If you use the ALTER TABLE statement to add a primary key, the primary key column (s) must already have been declared to not contain NULL values (when the table was first created). it's much more difficult with "classic" SQL - with window functions, it's quite easy.ĬOUNT(DISTINCT(status_to)) AS "Unique count" MySQL / SQL Server / Oracle / MS Access: ALTER TABLE Persons. Note that I have added 2 singleton values ( Single_1 and Single_2) to examine how one would, for example, count the DISTINCT values which had greater than 1 record in your table. Then populate it: INSERT INTO test VALUES You can do something like the following (all the code below is available on the fiddle here): CREATE TABLE test There's a far easier way to do what you want - I was thinking about this last night - see my second fiddle here. The HAVING clause is used with the SUM () function to filter the sum group where the total cost amount is greater than certain provided integer value as follows: Code 1 SELECT SupplierID, SUM (Unit CostEach) TotalCost FROM Suppliers GROUP BY SupplierID HAVING SUM (Unit CostEach)>200 ORDER BY TotalCost DESC Output: Example 5.
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