Andy Warren

I'm Andy Warren, currently a SQL Server trainer with End to End Training. Over the past few years I've been a developer, DBA, and IT Director. I was one of the original founders of SQLServerCentral.com and helped grow that community from zero to about 300k members before deciding to move on to other ventures.

Smart As A Bear?

by Andy Warren

SQLAndy

I got this at Hobby Lobby for $7 on sale, it’s about the width of a license plate and a...

2014-05-14

310 reads

Warrant Canaries & Transparency

by Andy Warren

SQLAndy

I recently ran across the warrant canary FAQ from the Electronic Frontier Foundation (EFF). The concept is simple – put up...

2014-05-14

544 reads

Drop Me? No, I Don't Think So

by Andy Warren

SQLServerCentral

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2014-05-14

2,215 reads

Discuss

Announcing the 2014 SQLSaturday Orlando Seminars

by Andy Warren

SQLAndy

On September 25, 2014 we’re pleased to have David Pless presenting an all day seminar on Enterprise Management and Monitoring...

2014-05-13

367 reads

Verizon PCI and Data Breach Investigation Reports

by Andy Warren

SQLAndy

If you deal with security and especially credit cards it’s worth spending an hour or two to read the 2014...

2014-05-13

437 reads

Notes From SQLSaturday #298

by Andy Warren

SQLAndy

The trip didn’t start smoothly for this one. Wed night I was really sick with some kind of stomach flu....

2014-05-12

425 reads

Writing Another Question of the Day

by Andy Warren

SQLAndy

The most recent one I wrote was a “question from error message” pattern. An experienced DBA should get it easily,...

2014-05-12

353 reads

Off to Jacksonville for SQLSaturday #298

by Andy Warren

SQLAndy

I’m looking forward to returning to Jacksonville after missing a year (or two?) to speak at SQLSaturday #298. I’m driving...

2014-05-09

334 reads

Speaking at MagicPASS on May 28, 2014

by Andy Warren

SQLAndy

If you’re wondering who the mystery speaker is – it’s me! I’ll be doing two presentations at Magic Pass on May...

2014-05-08

336 reads

Another User Has Locked My File!

by Andy Warren

SQLAndy

I had an SSIS package fail in a script task this morning. As part of the why process I opened...

2014-05-07

340 reads

Blogs

AI Innovation in Microsoft Keynote

I’m thrilled to be covering the Microsoft Keynote: Fuel AI Innovation with Azure Databases on Day...

Benefits of Migrating from Azure Synapse Analytics to Microsoft Fabric

Many customers ask me about the advantages of moving from Azure Synapse Analytics to...

PASS Summit 2024 – A Very Different World

By Brian Kelley

The last data centric conference I attended was the PASS Summit in 2019. A...

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Forums

What's New for the Microsoft Data Platform

By Steve Jones - SSC Editor

Comments posted to this topic are about the item What's New for the Microsoft...

Using Outer Joins

By Steve Jones - SSC Editor

Comments posted to this topic are about the item Using Outer Joins

Closest to ProcDate

Not sure I have this 2nd left join correct. I need to grab the...

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Question of the Day

Using Outer Joins

I have this data in a SQL Server 2019 database:

Customer table
CustomerID CustomerName
1          Steve
2          Andy
3          Brian
4          Allen
5          Devin
6          Sally

OrderHeader table
OrderID CustomerID OrderDate
1       1          2024-02-01
2       1          2024-03-01
3       3          2024-04-01
4       4          2024-05-01
6       4          2024-05-01
7       3          2024-06-07
8       2          2024-04-07

I want a list of all customers and their order counts for a period of time, including zero orders. If I run this query, how many rows are returned?

SELECT 
  c.CustomerName, COUNT(oh.OrderID)
 FROM dbo.Customer AS c
LEFT JOIN dbo.OrderHeader AS oh ON oh.CustomerID = c.CustomerID
WHERE oh.Orderdate > '2024/04/01'
GROUP BY c.CustomerName

See possible answers