Finding the number of times a particular value occurs in a set of records, or even the number of times a record is present in a table can be very helpful.
I found the query below and have used it several times. It’s simply, and easy to modify to suit.
SELECT YourColumn, COUNT(*) TotalCount FROM YourTable -- WHERE YourColumn = 'ThisValue' GROUP BY YourColumn HAVING COUNT(*) > 1 ORDER BY COUNT(*) DESC
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