Summary In this article, we will be looking at some of the useful techniques on how to reduce dimensionality in our datasets. When we talk about dimensionality, we are referring to the number of columns in our dataset assuming that we are working on a tidy and a clean dataset. When we have many columns […]
What do you think the top 10 Database DevOps trends in 2021 are? Redgate has condensed 3,200 survey responses from IT professionals worldwide into a handy infographic. Discover insights such as the top challenge in improving software delivery performance and the correlation between DevOps adoption and high-performing teams.
Greg Larsen continues his series and shows how user-defined roles roles can control SQL Server security.
Both Python and R have become very popular languages in the last few years, especially among data professionals. Which should you learn or use? Steve has a few thoughts.
Always Encrypted is a new security feature which was introduced in SQL Server 2016. Always Encrypted is a technology to ensure the data stored in a database remains encrypted at all times during SQL Server query processing. Always Encrypted allows clients to encrypt sensitive data, such as credit card numbers and national identification numbers, inside the […]
How to write idempotent DDL scripts that Flyway can run several times on a database, such as after a hotfix has already been applied directly to the production database, without causing errors.
Edward Pollack demonstrates how SQL Server plan cache mining can uncover a wealth of information to help with troubleshooting performance issues.
I want to show you how two common operators can deceive you into believing you have constructed a proper SQL statement for your solution. We may want to filter results in a table by using using a IN/NOT IN or a INNER JOIN/LEFT JOIN to another table. There are a couple of hidden dangers here […]
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I have this data in the dbo.Commission table in a SQL Server 2022 database.
salesperson commission Brian 12 Brian 16 Andy 7 Andy 14 Andy 21 Steve 20 Steve NULLAll the data is a varchar, and I decide to run this query to get the totals for each salesperson.
SELECT SalesPerson
, AVG(TRY_PARSE(Commission AS int)) AS TotalCommission
FROM commission
GROUP BY SalesPerson
GO
What average commission is calculated for Steve? See possible answers