This article explores the 'shadow copy' and 'disk virtualization' services built into the Windows operating system and explains a basic solution demonstrating how the technology is used to copy the data and log files for a live SQL Server database into an 'image', from which we can create multiple, lightweight copies, or clones, of the original database.
Learn how indexes can help you with more than just querying data.
I’ve seen the SQL EXISTS keyword in Microsoft SQL Server T-SQL code and don’t understand it well. What does it do? How do I use it? Are there best practices around SQL IF EXISTS?
Learn how ledger databases and ledger tables work in SQL Server 2022.
Open offices have an interesting side effect: less collaboration.
VIEWs are an undervalued and underused feature in SQL. They basically consist of a query that has been given a name, and a parameter list, so can be used like an inline macro. Technically, you’re supposed to think of it as a virtual table.
Why do I love editorials, I can hear you asking. The answer is simple. It's all about opinions. I have opinions. Lots of them. Lots and lots of them. I'm flying home from Hong Kong after visiting a Redgate customer. They are doing amazing work.. It's so cool getting to see how people are solving […]
This article shows how to use Python to create a REST API for your application that developers can use to access the database.
Learning is fundamental in technology. Steve has a few thoughts on adopting a new technology at work.
Most SQL bulk insert and SQL Server openrowset tutorials skip file access issues that can stop imports cold. Both the bulk insert statement and openrowset function rely on the SQL Server service account to read a source file. The SQL Server service account must have read permission on the file or its folder. It is also convenient to have read & execute as well as list folder content permissions.
By Steve Jones
I type fairly well. Well, I type fast, but I do wear out a...
By way of background, a while back I did video called “My New Favourite...
By ReviewMyDB
Index maintenance has always meant nightly jobs and a window you have to defend....
Comments posted to this topic are about the item SQL Art, Part 4: Happy...
WA:08218154393 Jl. Jenderal Ahmad Yani No.1, Benua Melayu Darat, Kec. Pontianak Sel., Kota Pontianak,...
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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