这句SQL语句我不太懂,为什么是>=呢?

xls901

SELECT Customers.CustomerID, Count(Customers_1.CustomerId) AS [Counter]
FROM Customers INNER JOIN Customers AS Customers_1 ON Customers.CustomerId>=Customers_1.CustomerId
GROUP BY Customers.CustomerId
ORDER BY Customers.CustomerId;
[em26]

INN

把>=改为 = ,< 或 <=运行一下看有什么结果就知到了.