TSQL, counting pairs of values in a table
Given a table in the format of
ID Forename Surname 1 John Doe 2 Jane 开发者_如何学运维 Doe 3 Bob Smith 4 John Doe
How would you go about getting the output
Forename Surname Count John Doe 2 Jane Doe 1 Bob Smith 1
For a single column I would just use count, but am unsure how to apply that for multiple ones.
SELECT Forename, Surname, COUNT(*) FROM YourTable GROUP BY Forename, Surname
I think this should work:
SELECT Forename, Surname, COUNT(1) AS Num
FROM T
GROUP BY Forename, Surname
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