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sqladventureworks

AdventureWorks practise questions - esp correlated subqueries


I am trying to hone my TSQL skills. I have downloaded the AdventureWorks database, but I could do with some example questions, the kind I would be asked in a real world business. Does anyone know of a list of questions out there for this database?

I am particularly interested in correlated subqueries. I adapted a question that a book I have presented. But in answering it I figured I could just use a left join and filter on the NULLS - I didn't need to use a correlated subquery. So I didn't get to practise one, and I still don't know when I would use them, or how my brain process would work if I was presented with a question that required a correlated subquery as opposed to a join (if there is such a thing).

Thank you in advance.


Solution

  • This not really a a question for this site, but as I was many times in your situation I will help you as I can.

    Make a query where you select all the clients that have no orders. I think this is the obvious example where you will need to use a subquery.