T-SQL : WHILE Loop Syntax
WHILE SomeConditionTrue
BEGIN
-- Execute code here
END
SQL: GROUP BY And HAVING
SQL GROUPING allows you to segregate data into groups so that you can work on it separately from the rest of the table records. Let's say you want to get the number of products in a category in the Northwind database Products table. You would write the following query: SELECT COUNT(*) NumberOfProductsByCategory FROM Products GROUP BY CategoryID The query above gives you the following results: The query gives you the number of products in each category, however it's not very useful. You don't really know what category the count is for in each record. You might want to try to change the query into something like this: SELECT CategoryID,COUNT(*) NumberOfProductsByCategory FROM Products GROUP BY CategoryID The above query is more useful the preceding one, however it only gives you the CategoryID number not the CategoryName in the Categories table. Being the perfectionist that you are you say to yourself, I can do better. "Yes, I can". I think that was a ca
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