External Article

PostgreSQL Constraints: Learning PostgreSQL with Grant

One of the most important aspects of data management is the ability to ensure that the data in your database is well defined and consistent. Some aspects of that are ensured through the relational data structures you design. Another piece of control is using the correct data type. Then, we get to constraints. A constraint is a way to validate data prior to adding it to your database. This is one more tool in the toolbox that helps you maintain good data.

External Article

The future of AI in solving database challenges

The conversation around Artificial Intelligence (AI) is not a new subject to the database space, but the recent rise in machine learning tools like ChatGPT have sparked increased focus on new ways to simplify existing DBA challenges.

Join Redgate’s own DevOps Advocate, Steve Jones, along with webinar guests Kellyn Pot’Vin-Gorman (Principal Cloud Solution Architect, Microsoft) and Brian Randell (Product Marketing Director, Github) to discuss how AI could help manage complex database ecosystems.

SQLServerCentral Editorial

The Human Factor

A week ago I was in Pasadena attending the SCaLE 20x conference, a gathering of many different open-source communities discussing the technologies and platforms that draw them together. I was fortunate enough to hear some excellent presentations on PostgreSQL and give two talks as well. After the first round of talks on Friday morning a […]

Blogs

T-SQL Tuesday #180: Good enough is perfect

By

How can you achieve good enough without compromising the process/product? In the world of...

How to Convert FileTime to DateTime

By

One of my customers recently wanted to rename each of the SQL audit files...

The pros and cons of self-service BI: What every industry leader should know

By

The post The pros and cons of self-service BI: What every industry leader should...

Read the latest Blogs

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

By boehnc

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

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