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.

Notes From the January 2014 MagicPass Meeting

by Andy Warren

SQLAndy

I went 30 miles south last night for the first meeting of the year. Extra good night because I was...

2014-01-16

483 reads

A Server Bench

by Andy Warren

SQLAndy

This past weekend I was doing some early Spring cleaning and decided it was time to throw out two old...

2014-01-15

626 reads

Should You Run For the PASS Board? How Do You Decide?

by Andy Warren

SQLAndy

Here are some of the questions I ask when someone is thinking about running for the Board:
Are you eligible? Read...

2014-01-15

541 reads

Two-Factor Authentication

by Andy Warren

SQLAndy

Something you have and something you know – that’s the heart of two-factor, sometimes called multi-factor, authentication. RSA was for years...

2014-01-15 (first published: 2014-01-09)

6,319 reads

Google Buys Nest

by Andy Warren

SQLAndy

I was a bit sad to see that Google bought Nest. I like upstarts that see a problem and solve...

2014-01-14

626 reads

Time to Plan For Running For The PASS Board

by Andy Warren

SQLAndy

I know it’s only January, but if you’re at all considering being a candidate you need to get going now....

2014-01-14

433 reads

Bradley Ball at MagicPASS on January 15, 2014

by Andy Warren

SQLAndy

First meeting of the year with Bradley Ball presenting Locking, Blocking, Latches, Deadlocks, and Spinlocks. Let them know you’ll be...

2014-01-13

659 reads

How To Campaign For the PASS Board

by Andy Warren

SQLAndy

Let’s say you’ve decided to run, good! What do you do next? I’m not going to give you a blueprint...

2014-01-10

387 reads

The SQLSaturday Wiki–Revisited

by Andy Warren

SQLAndy

I saw a discussion on Twitter yesterday where Kendal Van Dyke referenced the SQLSaturday wiki as a resource, I thought...

2014-01-10

380 reads

Changes to PASS Voting Eligibility

by Andy Warren

SQLAndy

There was a blurb in the Connector today about an eligibility change for voting. The “change” is a requirement to...

2014-01-08

380 reads

Blogs

Day 2 at PASS Data Community Summit 2024

I missed blogging yesterday as I was on stage/backstage for quite a bit of...

PASS Summit 2024 – Wednesday

By Brian Kelley

A common theme in the PASS Summits I've attended is community and that's definitely...

Taming Database Challenges: Insights from Redgate Keynote

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

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Forums

Deduplicating rows by choosing the row with the shortest string

Hello T-SQL experts I have a table containing team codes and descriptions. Unfortunately, many...

query help

I need some help to optimize this query as it runs in many threads...

Unencrypted connections in Always on Availability Group

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

Visit the forum

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