The Bit Bucket

In previous posts, we’ve seen how to query tables. Another type of object that you might need to query is a table-valued function.

Table-valued functions (TVFs) are predefined code i.e., somebody’s written the code, and they take parameters, but they return row set of data, much like a table.

So in the example above, I’m saying I want to declare a Cinema ID variable, and I’ve said let’s have Cinema 27. Then I’ve said I wanted to select from GetRecentOrders. It’s  a TVF that takes two parameters: the Cinema ID, and the maximum number of orders to return. In the case, I’ve said that I want the last two orders for cinema 27.

2025-02-12

This is a post in the SQL Interview series. These aren’t trick or gotcha questions, they’re just questions designed to scope out a candidate’s knowledge around SQL Server and Azure SQL Database.

Section: Security Level: Intro

Question:

SQL Server can use both logins and users.

What is the difference between them?

Answer:

A login provides access to the server, but not necessarily to any databases.

A user is used to provide access to a database. It might be mapped to a login, but it is possible for databases to authenticate users directly.

2025-02-11

I recently listened to the audio book of Preincarnate by Shaun Micallef.

I need to start by saying that I’m a huge fan of Shaun’s, and I also love hearing him narrate books. Shaun’s humour can be a matter of taste. It’s not for everyone, but I generally love it, although I know many others that don’t. Mad as Hell was one of my favourite TV shows. The one exception is that I wish Shaun would lose the impersonations of Kenneth Williams.

2025-02-10

Another Fabric Down Under podcast is out the door.

This time, the guest was Minni Walia.

Minni is a Principal Program Manager with the Microsoft Fabric Customer Advisory Team (CAT), specializing in the Real-Time Intelligence capabilities within Fabric.

Minni has over 20 years in tech, and has extensive experience in developing applications and data platforms. She spent more than a decade as an Enterprise Architect before transitioning into data analytics and engineering roles at Microsoft.

2025-02-10

Another interesting operator is INTERSECT. We saw how EXCEPT takes a set of rows and removes any duplicates, and removes any rows that are also contained in a second set of rows.

INTERSECT is similar in the way it works, but it only returns the rows that are common to both row sets.

You could replace an INTERSECT statement with a WHERE EXISTS clause but if you need to deal with NULLable columns, and as the number of columns increases, you can see that INTERSECT becomes quite an elegant solution.

2025-02-10

Our free SDU Tools for developers and DBAs, now includes a very large number of tools, with procedures, functions, and views. One request that we had some while back, was the ability to format phone numbers using Australian phone number format. To make that easy, we added the FormatAustralianPhoneNumber function.

The only parameter for this function is the phone number that needs to be formatted.

It starts by finding any digits. Then if it finds either 6, 7, 8, or (the standard) 10 digits, it formats the number appropriately.

2025-02-09

We saw how UNION and UNION ALL worked in the last T-SQL 101 post. Sometimes you want to work with two (or more) row sets in other ways.

The EXCEPT clause says that I want all the distinct entries in the first row set unless they also exist in the second row set.

In some database engines, this operator is called MINUS, but EXCEPT is the ANSI SQL standard, and that’s what SQL Server uses.

2025-02-09

Our free SDU Tools for developers and DBAs, now includes a very large number of tools, with procedures, functions, and views. Applications often need to display a list of languages for users to choose from. To make that easy, we have now included a view called Languages.

The Languages view returns details of all the world’s languages, based on ISO 639-1. For each language, the view returns:

• FamilyName
• LanguageName
• NativeLanguageName
• ISO2CharacterCode
• ISO3CharacterCode

The FamilyName indicates the group of languages that the language belongs to. The LanguageName is what we call it in English. The NativeLanguageName is what locals call the language. And then there are the 2 and 3 character codes from the ISO standard.

2025-02-08

There are times when you need to connect together two sets of results into a single result set. The UNION statement is the way we do that.

In the example shown above, I have two SELECT queries. Notice that I could just highlight either one of them, and run them, and I’d see those values. But if I run the whole query, I’ll get back a single set of results that combines data from each of the queries. Note the results:

2025-02-08

Our free SDU Tools for developers and DBAs, now includes a very large number of tools, with procedures, functions, and views. Excel is fascinating in how it stores data. I have friends who joke that everything in Excel is a number or a string, and anything else you see is an illusion.

Date and time values in Excel are odd and use what most call a serial number when they’re stored. It’s common to need to import values from Excel into SQL Server and to export values to Excel.

2025-02-07