A Night at the Movies: Unlock Power Query Secrets, Inception-Style!🍿🎬

Recently, I found myself re-watching one of my all-time favourite movies, "Inception." It's a mind-bending tale of dreams nested within dreams. And it got me thinking, isn't that quite like lists in Power Query? Stay with me here!

Power Query Meets Inception 🤯

Just like in "Inception," where you can go deeper into multiple layers of dreams, in Power Query, you can create lists within lists. Yep, welcome to the world of Listsception, (it’s just a term dubbed by me - perhaps Microsoft will add it to their library 😝).

What Makes Lists So Great? 🌟

Lists are the unsung heroes in Power Query, often serving as the input to other functions. By understanding how to create lists, you can unlock a more efficient way to manipulate your data and If you want to be a Power Query Pro, you need to know your lists!

The Building Blocks 🧱

But first let’s lay the foundation. If you've been experimenting in M Code, creating a list is pretty straightforward. You can simply use the curly brackets for this. Take a look:

Voila! You've got yourself a list.

Taking the Plunge: Nested Lists (or 'Listsception' for the Film Buffs) 🌌

So, lists aren’t just a basic function in Power Query? Nope! That's like watching "Inception" and thinking it's just about people taking really long naps. If you haven't seen the movie, I not-so-humbly suggest you watch it; it's an all time favourite of mine. And trust me, once you've seen dreams within dreams, you'll completely understand why I’m so excited about lists within lists—or 'Listsception.'

Behold, Listsception! 👇

From Table to Listsception 📋

You can also create a list of lists from a table in Power Query. Start with a table and then dive in using =Table.ToRows()

This will turn your table into a nested list.

What Can You Do With These Lists? 🛠️

So lists are definitely the backbone to your Power Query functions. Here are a few ways in which you can put these lists into practice:

• Replace Values: Once you’ve created your lists, you can use them to replace any list of lists, by using them to dynamically change column names.

• Parameterize Queries: You can use lists to feed parameters into your queries, making them more dynamic. 

• Looping & Iterations: When you want to iterate through rows, lists can be your go-to structure, especially when used with functions like List.Accumulate.

• Dynamic Operations: When paired with other functions, lists can be part of more complex, dynamic queries, like List.FirstN where the “N” can be parameterized. If you would like to watch List.FirstN in action and how it’s used to create running totals please click here.

• Aggregations: Lists come in handy when you need to perform aggregate operations like sums, averages, and counts across a data set.

• Sequencing and Indexing: Need an ordered sequence? Lists have your back. You can generate sequences for indexing and other operations that require ordered data.

Comment of the Day

Please click here if you would like to watch the video that YvesAustin is referring to, it shows you how to use lists to replace an entire set of transactions.

I would love to hear if you enjoyed today’s newsletter, please hit reply and let me know:

• 💌Loved it!

• 😐It’s okay

• 👎Do better

Also if there’s anything you would like me to cover please let me know.

If you missed last week’s newsletter, you can check it out here. We delved into the critical step for safeguarding your data integrity. Bypassing this could leave your data open to scrutiny and questioning it’s reliability. Don’t let that be you.

Wrap Up and Next Week's Teaser 🌟

Alright, Query Wizards, that's it for this week. Lists, like dreams in Inception, are powerful tools for constructing your own realities in Power Query!

👀 Sneak Peek for Next Week: We’re exposing the single, sneaky step that’s silently sabotaging your queries. It’s often the step you least expect! Don’t miss it - your queries will thank you!

Thanks for reading. Until next week!

Miss Microsoft