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.

Blog Post

Spring in Florida

The first sign of spring in Florida is the leaves falling from the oak trees. Tons of leaves, leaves everywhere,...

2014-02-27

1,044 reads

Blogs

Taming Database Challenges: Insights from Redgate Keynote

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I am excited to cover the Microsoft Keynote on Day 2: Redgate Keynote: Simplifying...

AI Innovation in Microsoft Keynote

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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

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

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Forums

Unencrypted connections in Always on Availability Group

By Awais Afzal

Hi, In my Always On Availability environment, I am seeing two encrypt_option values as...

Error loading multiple CSV files in SSIS

By water490

Hi everyone I have a bunch of CSV files that I need to bulk...

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...

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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