We are hiring a DBA at my company Corzen and instead of looking at resumes/cvs we are looking at how people solve particular SQL problems-not just the solution but the approach they take. (Do you use temp tables, (nolock), CTEs, table alias, etc.)

Here are the five test questions we ask. (If you want to come work here, just email me the answers.)

Here are three TSQL problems that can judge how you approach a SQL problem. There are no real wrong answers, but the more efficient and bulletproof the query is the better. No cheating and no cursors! Don't cheat and don't google the answers (we'll know.)

Step 1: run SetupTSQLProblems.sql in any database.

Problem 1.

Finding Duplicate Products in the Product table. Write a query to list only the duplicated products in the Products table. Assume that the dupe is the product with the highest Product_ID. The results of your SQL statement should be:

Dupe_Product_ID	Dupe_Product_Name	Dupe_Price	Parent_Product_ID	Parent_Product_Name
7	Widgets	88	1	Widgets

Problem 2.

Assign rooms to classes based on capacity using the Classes and Rooms tables. Rules: each class should have a room (and NULL if a room is not available). No class can be in a room where there are more students than capacity. No room can be used twice.

The results of your SQL statement should be:

class	students	room	capacity
Advanced SQL Queries	65	225	70
Introduction to C#	52	224	60
XQuery Deep Dive	35	222	40

Problem 3.

Make the following static pivot dynamic in AdventureWorks, assume that the orderyear can increment to 2005 and 2006. Assume that order years can skip.

SELECT *

FROM (SELECT CustomerID, YEAR(OrderDate) AS orderyear, TotalDue

      FROM Sales.SalesOrderHeader) as Header

PIVOT(SUM(TotalDue) FOR orderyear IN([2002],[2003],[2004])) as Piv

Problem 4.

You have a piece of XML:

<office id="NYC">

  <Employees>

    <employee num="1">Steveemployee>

    <employee num="2">Alemployee>

    <employee num="3">Mikeemployee>

    <employee num="4">Malishaemployee>

  Employees>

office>

<office id="Cairo">

  <Employees>

    <employee num="1">Remonemployee>

    <employee num="2">Lameesemployee>

    <employee num="3">Bassmaemployee>

  Employees>

office>

<office id="Pune">

  <Employees>

    <employee num="1">Vinayemployee>

    <employee num="2">Pradeepemployee>

    <employee num="3">Rashmiemployee>

    <employee num="4">Sujataemployee>

    <employee num="5">Ajitemployee>

  Employees>

office>

<office id="Karachi">

  <Employees>

    <employee num="1">Amratemployee>

  Employees>

office>

A. Using the XML datatype, write an XQuery to return the 3^rd employee in the NYC office. Your results should look like:

EmployeeName

Mike

B. Using the XML datatype, write an XQuery to return the 3^rd employee in each office. Your results should look like:

EmployeeName

Mike

Bassma

Rashmi

Problem 5.

Using adventureworks, rank each salesperson by total sales in 2004 with the rank starting over for each country. Do not use temp tables, self joins, or cursors.

CountryName	SalesPersonID	TotalSales	SalesRank
Australia	290	955311.5851	1
Australia	288	35006.4385	2
Canada	285	2411105.152	1
Canada	278	755593.2997	2
Canada	268	15655.2241	3
France	286	1832662.467	1
France	284	2278.3269	2
Germany	289	1121896.781	1
Germany	284	74363.4408	2
United Kingdom	282	1648152.541	1
United Kingdom	284	54036.9765	2
United States	276	2534645.3	1
United States	275	2053782.757	2
United States	277	1824701.882	3
United States	279	1446386.797	4
United States	281	1429353.893	5
United States	287	1114278.877	6
United States	283	901142.2512	7
United States	280	871513.6294	8
United States	268	318200.2683	9

Enjoy!