Fix: Excel Formulas don’t update in Power Query tables

If you’re new to Power Query, chances are you’re more comfortable doing tricky mathematics using Excel formulas, rather that Power Query formulas.  No shame there, but you’ve probably run into a situation where you set up the formulas, refresh your query and the Excel formulas don’t update in Power Query 's output table.

I’ve worked with this issue for a long time, and it’s actually caused me to avoid using Excel formulas in tables generated via Power Query all together. Having said that, there is now an easy way to fix this which renders that avoidance obsolete.

The Issue:  Excel Formulas don't update in Power Query tables

Let’s take a quick look at this scenario.  We have a simple table called Animals as follows:


And it gets landed in another table.  But in this table, we added a new column called “Est” to the end, which holds the following formula: =[@Price]*[@Quantity]


So far so good, but what happens when we add a new line to our Animals table and refresh it?


Plainly, this is not good at all!

The Fix:  Excel Formulas don't update in Power Query tables

The fix is remarkably simple, once you know what to do:

Step 1: Change the Table Design Properties

  • Select any cell in the OUTPUT table (the green one)
  • Go to Table Tools –> Design –> Properties (External Table Data group)


  • Check the box next to Preserve column soft/filter/layout and click OK


Now, at this point, nothing appears to change.  In fact, even refreshing the table seems to make no difference.

Step 2: Ensure the Formulas are consistent

The reason the formulas didn’t fill correctly for us is different now.  It is entirely based on the fact the formula in the last column is no longer consistent.  Naturally, that means that Excel won’t auto-fill the formula, as it doesn’t know which is correct (the formulas or the blank cell.)  We need to fix that before this will work for us.

  • Using whatever method you want, ensure the formula is consistently applied to each cell down the column

Our data should now look something like this:


Step 3:  Test it

And now, when we add new data and refresh the Power Query…


Wrap-up Thoughts

On my Excel 2016 this behavior is now default.  I don’t know when it changed, to be honest.  And if your behavior is different, I’d love to know.  I’m running the Office Pro Plus subscription – first release.

On Excel 2010/2013, the old default of not updating the tables appears to prevail.  It’s actually for this reason that I covered this, as it came up as a question in my Power Query forum.

I’m not sure if this is good or bad, but this setting can/must be managed for each output table individually.  There doesn’t seem to be a way to set one behavior or other to apply to all tables.  To be honest, I think they’ve got it right in Excel 2016, so at least it’s fixed if you’re current.  (And for reference, my understanding is that this required a patch to Excel, not Power Query, which is why I suspect that we likely won’t see it fixed for Excel 2010/2013.)

July 2016 Power Query Update

Hey folks,

I'm actually on vacation, so this post is going to be short.  I just wanted to make sure you all are aware that there is a new Power Query update available.

New features in the July 2016 Power Query update:

  • New SAP HANA connector.
  • New SharePoint Folder connector.
  • New Online Services connectors category.
  • Improved DB2 connector, now leveraging the Microsoft driver for IBM DB2.
  • Improved Text/CSV connector, now exposing editable settings in the preview dialog.
  • Improved relational database connectors, now including Schema information as a part of the Navigation hierarchy.
  • Data Source Settings enhancements, including “Change Source” capability.
  • Advanced Filter Rows dialog mode within the Query Editor.
  • Inline Input controls for Function invocation within the Query Editor.
  • Support for reordering Query Steps within the Query Editor by using drag and drop gestures.
  • Date picker support for input Date values in Filter Rows and Conditional Columns dialogs.
  • New context menu entry to create new queries from the Queries pane within the Query Editor.

My Thoughts (without actually using it yet)

Now you can get full pictures at the official blog from Microsoft, but I'll just call out a couple that I think are pretty darned important from a usability perspective.

  1. Continuing with last month's update where we got Drag and Drop for the query groups, we now get Drag and Drop for the query steps.  That is just plain AWESOME.
  2. The new Advanced Filter dialog looks pretty good.
  3. The Date Pikcer also looks pretty helpful.
  4. A context menu to create new queries is also SUPER helpful.  One thing I'd like to see added here, is the ability to set each new query to load to connection/table/data model from INSIDE the query editor.  (Currently, the choice you make is applied to ALL new queries - the main reason I have my defaults set to load to connection only.)

June 2016 Power Query Update

Yesterday, Microsoft released the June 2016 Power Query update.  Even though there are only four items on the list of new features, some of them are quite impactful.

What’s new in the June 2016 Power Query Update

The four new features are:

  • Conditional Columns
  • Column type indicator in Query Editor preview column headers
  • Reorder Queries and Query Groups inside Query Editor via drag and drop gestures
  • Query Management menu in Query Editor

Microsoft has a blog on this here, but let me hit these quickly in reverse order to give my comments as well:

Query Management Menu in Query Editor

Honestly, to me this is kind of a throw away waste “button for the sake of a button” kind of feature.


Does it make things more discoverable?  Maybe.  But we can get to all these features by right clicking the query in the Queries pane on the left of the editor.  Personally, I would have rather seen them give me a feature to “pin” the Queries pane open and set that as a default, as I find the navigation from that area much more useful:



Reorder Queries via Drag and Drop

This is great… so great in fact, that the only real question is why it hasn’t worked in the past.  Time & resources is the answer, but it’s now working the way you’d expect it to work.


PS, if you don’t know how to group your queries, right click on one, say “Move to Group” and select New Group.  Pretty handy for keeping things organized.

Column Type Indicator

This is BY FAR the most important of the upgrades.  The reason is that this has been a deadly area of weakness since day one.  If you’ve ever been burned by an “any” data type, you know why.  And if you haven’t… hopefully this will help ensure you don’t.

We can now plainly see which columns have been defined with each data type:


Notice how easy it is to tell that the “Client, Task and Notes” fields are text (as shown by the ABC icon in the column header.)  Hours is a decimal number, rate is a whole number, and Date… is undefined.  That one needs attention as indicated by the question mark.  Very visual, and very badly needed for  a long time.  This one feature is, in my opinion, worth the upgrade.

Conditional Columns

This is also a pretty cool feature, as it lets a non-coder build an if then else (if) statement.  Full caveat here: this is the image from the official Microsoft blog, not one of mine, but it shows you the general idea:

June-2016-updates-for-Get-Transform-in-Excel-2016-1.png (1282×809)

As cool as this is, there are some issues here:

  1. You can only feed out full columns as outputs, not formulas/equations.  So if I wanted to check a column and return [Hours]*[Rate] in one case and [Hours]*1.5*[Rate] in others, it won’t work.  (Instead I’ll get text.)  To do that you’ll still need to write your formulas manually.
  2. You can’t provide IFERROR style logic to check if something errors and react accordingly.  To do that you’ll still need to create your own custom column formula using the “try otherwise” formula.
  3. Assume you created a custom column using the “Add Custom Column” button, and manually wrote your “if then else” formula.  You then committed it and want to change the logic, so you click the gear icon in the applied steps window… and you’ll be taken to the Conditional Column interface shown above, not the original window where you can create more complex logic.  So if you want to modify that formula to be more complex than this new interface allows, you’re now going to have to go to the Advanced Editor window.  I have suggested to Microsoft that they need a button to return is to the previous interface for this scenario.

Despite the shortcomings, we should recognize that this is a great new feature.  You can test if one column compares (match, doesn’t match, greater than, etc) another column or specific value without having to manually write any M code formulas.  You also aren’t obligated to feed out a column’s value, but rather can feed out text or values too.  So as long as your logic needs are fairly simple, you can use this feature.

Download the June 2016 Power Query update

You can pick it up from Microsoft’s site here:

Also, I’ve started holding on to the previously released installers should you ever need to regress to a prior version.  You can find the installers I have in my forum here:

New Vancouver Power BI User Group

I’ve been thinking about this for a while and, after discussing it with a couple of others who are passionate about Power BI…  I’m pleased to announce that we have created a new Power BI User Group in Vancouver, BC!

What is the Power BI User Group about?

The goals of this user group are fairly simple:

We plan to meet monthly, and have a presentation on using Power BI technologies.  (This could be Power BI Desktop, Excel, Power Query or Power Pivot.)  Whatever it the presentation, and no matter how focussed it is on a specific area, it will ultimately be relevant to the over-arching Power BI path of taking your data from raw form to a published dashboard.  This user group is basically dedicated to bringing you content to inspire you and make you an expert in the Power BI technologies in your company.

Our secondary goal is to be a networking group for Power BI professionals.  If you’ve ever felt like the only one in your company that actually understands what you do… well that’s why we are here.  To give you someone to swap stories with, get ideas and maybe even change your career goals.  🙂

Oh… and did I mention that another goal we have is to keep these events free for attendees?

How can you get involved?

There’s actually a few ways you can get involved with us…

If you’re looking to attend…

Then it’s simple.  Sign up at our Meetup site.  Then attend a meeting. That’s it.  No cost, no fuss.  All we ask is that you register in advance and attend if you say you’re coming.  (We have limited space in our venue right now, only able to seat about 25 people.)

If you’d like to sponsor the event…

We are looking for a sponsor to cover the cost of pizza and soft drinks for our user group attendees.  It shouldn’t be much, and we’d be happy to tell everyone how awesome your company is.  If you’d like to come on board as a sponsor, please get in touch with me via my contact form.

If you’d like to speak…

Got something cool that you’ve built using the Power BI technology stack?  Would you like to talk about how to actually get Power BI traction in a corporate environment?  Got some other relevant topic that you’re passionate about?  Come to an event and chat with us.  One of our key goals is to make sure we have good variety in our speakers!

When is the first meeting?

Great question!  We’re going to be meeting Thursday, July 14 at 5:30pm in downtown Vancouver.  I’ll be presenting on how to build this self updating Power BI dashboard which is originally sourced from PDF files.

Keep The Most Recent Entry

This week’s post was inspired by a question in my Power Query help forum.  The poster has a set up data, and needs to keep the most recent entry for each person from a list of data.


I never saw the user’s real data, but instead mocked up this sample, which you can download here:


Obviously it’s fairly simple, and the key thing to recognize here is what we’re after.  What the user needed was this:


As you can see, we want to keep the most recent entry only for each person.  In the case of Fred and Mark that is Mar 31, but Jim didn’t have any activity for March, with his last entry being Feb 29.  So how do we do it?

1st attempt to keep the most recent entry

I figured this was pretty easy, so advised the poster to do the following:

  1. Pull the data into Power Query
  2. Sort the Date column in Descending order
  3. Use the Remove Duplicates command on the Student column
  4. Give the query a name (I called mine “Unbuffered” for reasons that will become clear)
  5. Load it to the worksheet

Easy enough, right?  Except that we actually got this:





Huh?  What the heck is going on?  I tried changing the dates to text in an attempt to steal away Power Query’s ability to sort based on dates.  (Okay, it was a shot in the dark, and it didn’t work.)

As it turns out, the “Table.Distinct” command that is used to remove duplicates IGNORES previous sorts, going back to the original data sort order.  I’ll admit that this completely shocks me, and is not at all what I’d expect.

So how do you keep the most recent entry?

There’s a few potential ways to deal with this:

  • Sort the data before it comes into your query.  This could potentially be done in a staging query, via a SQL sort command or some other method.  The challenge is that this isn’t always practical (using that custom SQL query breaks query folding, right?)
  • Issue some kind of command (like a group by) that creates a new table which is already sorted in the correct order.  Again, this would work, but really seems unnecessary unless you have some other need to do so.
  • Sort the table, then buffer it before removing duplicates.

Huh?  “Buffer” it?

Using Table.Buffer() to help keep the most recent entry

I’m not a master of explaining Table.Buffer() (yet), but basically you can look at it like this:  It pulls a copy of the table into memory, preventing Power Query from recalculating it.  This can be super useful if you’re passing tables to functions, but in this case can help us lock down the previous query steps before applying the duplicate removal.  When the query state is buffered, that is the “most recent” copy that Power Query will revert to.

Rather than adjust the previous query, here’s what I did in order to create the working solution:

  • Duplicated the “Unbuffered” query
  • Renamed the new query, calling it “Buffered”
  • Selected the “Sorted Rows” step we generated (just before the “Removed Duplicates” step
  • Clicked the fx icon in the formula bar


As I’ve mentioned a few times on this blog, this creates a new step that simply refers to the previous query step.  I then just wrapped the text for the new Custom1 step in the formula bar with Table.Buffer():



And when you hit Close & Load, you get a different result that our previous query… you get the result we actually wanted:


So what’s happening here?

First, just to be clear (before Bill or Imke call me out on this), inserting the new step wasn’t entirely necessary.  I only did this to demonstrate the key difference in a distinct step of it’s own.  I could have easily just wrapped the Sorted Rows step in Table.Buffer() and it would have worked fine.  🙂

The key difference here is that the Table.Distinct() command we use the Removed Duplicates step will go now only go back so far as the buffered table.  From the Excel user’s perspective, it’s kind of like we’ve been able to copy all the steps before this, and lock them in with a PasteSpecial command, and point Power Query to that version of the data instead of looking back at the original.

Cool!  I’m going to use Table.Buffer everywhere!

Um… don’t.  That’s actually a really bad idea.

Table.Buffer() needs to be used with a bit more care than that.  Every time you buffer a table, it needs to be processed and written into memory.  That takes resources.  You only want to use this command when it makes sense.  Some places where it does:

  • When you need to lock down previous steps to prevent things being ignored, like in the case above
  • When you want to pass a table to a function.  If you don’t buffer it first, the table may get re-calculated/refreshed before being passed into the function.  If you’re doing this for every row, that can be a lot of re-calculations.  In this case it may make sense to Buffer the table, then send the buffered table into the function.  Even though the buffering takes overhead, it only happens once, which can speed things up

Just also remember that the instant you buffer your table, you break any query folding ability, as the data is now in Excel’s memory space.  Something that is worth consideration if you’re doing large operations against a database.

Cartesian Product Joins (for the Excel person)

While I was at the PASS BA conference in San Jose, CA last week, I got an email from a reader asking if Power Query could create a Cartesian Product join.

Now I’m an Excel guy, and I’d never heard this term before.  Fortunately, I got the email while I was sitting around the table with a few of my geeky friends, many of whom came from the database world.  This was cool as their answer wasn’t “What is that?”, it was “Why would you want to?”  (As it turns out, there are some VERY good uses for this technique.)

Regardless, mine is not to wonder why, but rather to see if things can be done.  And, as you might expect, we can absolutely create a Cartesian Product (or Cartesian Square)using Power Query.  And actually, it’s REALLY easy when you know how.

Cartesian Product for the Excel person

So what the heck is a Cartesian Product anyway?  (Besides being really hard to spell!)

Picture you have two lists:

  • Automobile make
  • Paint colours

Plainly the two are not related in any classic kind of term.  (How do you match red to Dodge Ram?)  But assume that we can paint any vehicle we have any colour of paint we have.  Of course, that’s done at the factory, so we need to make a product list that shows all of our possible combinations:  Dodge Ram – Red, Dodge Ram – Blue, Dodge Ram – Black, etc…

So basically, for each row on the Vehicle Make table, we need to assign every colour that exists in the Paint Colours table.

If you’d like to read more about this join/math, there is a good article on Wikipedia explain it.

Creating a Cartesian Product in Power Query

To illustrate this, I’m actually going to use a deck of cards, as shown in the Wikipedia article I referenced above.  So we have two tables, as shown below:


(That’s table “Cards” on the left and table “Suits” on the right)

And now, what we want to do is create a join so that we get each suit assigned to each card.  (We could do this the other way around too, or we could just sort it after.  Either way gets us to the same place in the end.)

Setting up the Tables

So the first step is to set up the tables.  To do this we simply pulled each table into Power Query and set up the query as a connection only query.

  • Click in the appropriate table
  • Create a New Query –> From Table
  • Right click the only column –> Change Type –> Text
  • Home –> Close & Load –> Close & Load To… –> Only Create Connection

We should now have two queries in our workbook that are pointers to the underlying data:


Now, let’s set up a new query that references the cards query:

  • Workbook Queries Pane –> right click Cards –> Reference
  • Rename the query to “52 Card Deck”

Awesome, we’ve now got a simple query all ready to go:


Creating the Cartesian Product

The trick now is to create the Cartesian Square.  You’d think this would take some weird Voodoo magic, but it’s actually SUPER simple… just different than normal.  We can’t fall back on the whole “merge tables” experience, as we’d need to pick matching values between the columns… and their aren’t any.  For this reason, none of the join types I discuss in either of these articles will work:

So how do we do it?  Like this:

  • Add Column –> Add Custom Column
  • In the formula area, enter “Suits” (with no quotes)

Did you see what we did there?  We asked Power Query to provide the Suits table for each row of our cards table.  The result is a table of tables which – when you click in the whitespace beside the Table keyword – you can see contains our suits:


The final step is to click that little expand icon on the top right of the Custom column (clear that default prefix checkbox as you do) to expand those records.  And the result is a completed table where each card has all four suits.




Not bad… no need to write any funky formulas, fill up or anything.  🙂

Sample Workbook

If you’d like to download the sample workbook, you can find it here.

(Now I just hope that when I want to find this article that I can remember how to spell Cartesian correctly!)

32 Bit Excel Memory Limit Increase!

So this is just huge, especially if you work with Power Pivot models and are stuck in 32 bit Excel… Microsoft has just released a 32 bit Excel Memory Limit increase for users of Excel 2016, effective build 16.0.6868.2060 (which is the current build for the Insiders program.)


UPDATE:  Effective June 7, 2016 (and build 15.0.4833.1000), there is now a patch available for Excel 2013 (both MSI and subscription versions).  More info here:

Why a 32 Bit Excel Memory Limit increase?

Users stuck on 32 bit Excel were limited to only using 2GB of RAM for their Excel/Power Pivot models, no matter how much memory was available on the PC.  The answer to this in the past was to install the 64 Bit version  of Excel, as that could address up to 8 TB  of memory (if you had it, of course.)

There has been a hack/patch available for a while, (see below,) and I spoke to a user at the PASS BA summit who told me that without that he simply couldn’t use Power Query at all.

How big an increase is it?

Before you start thinking that you’ll now get the same memory access as with 64 bit Excel, let’s disabuse you of that notion.  It’s better, but not parity.  How much you get actually depends on the bitness of your operating system.

  • 32 bit Windows:  up to 3 GB
  • 64 bit Windows:  up to 4 GB

I suspect the first is an operating system limit and that the second is probably more of an internal architecture decision.  The world needs to move to 64 bit, but this will help give companies (even more) time to make that move.

What about non-Power applications?

This change doesn’t just benefit Power Pivot and Power Query; it benefits anyone who has been running into memory constraints.  So if you’ve been running out of memory because you’ve been pushing huge data sets via VBA/SQL, you’ll love this too.

How about Excel 2010/2013?

Yeah, no.  Sorry.  This is part of the benefit of being current… Microsoft is building for the current version of Office.  Excel’s biggest competitor is previous versions of Excel, so by providing a fix like this to a prior versions they’d actually be giving you reasons NOT to upgrade.  You’re in business, and I’m sure you understand that – as much as this sucks for you right now – you’d probably make the same call.

Having said that, if you want to install “the patch” to get your access in previous version, Rob Collie has a link to it in point 3 of this article.

The “Official Word” from Microsoft…

You can find that be reading KB3160741 for more details.

Map Columns Between Data Sets


Ken is at the PASS BA conference this week, so it seemed like a perfect time for me to publish my first Power Query post here.  In this installment, I'm going to show how to map columns between data sets.

Exploring how to map columns between data sets

I’m on a great new project where Power Query is the bread and butter of the solution. We’re pulling design information from Engineering Design Systems and building transforms to load into another engineering application. This application has a very strict requirement for data layout. Needless to say, the data structures and field names are seldom consistent between the two applications, so a key part of the transform is to map columns from one data set to the other.

Generally, Power Query’s ability to insert, rename, and move columns is useful in a case like this, however we are doing this for a large number of different data transfers, developing the maps in an ongoing process, and I REALLY don’t want to rewrite the Power Query steps for every change in every transform. (Also being able to document the transform is important for design and debugging).

Here’s a simplified example:

Source Data: The Flintstones

The Flintstones Sample data in a small table provides the source of data to be mapped 1

Target Data Structure: M*A*S*H

What does M*A*S*H have to do with the Flintstones? Not much really, that’s the point. But I want to convert data to this layout.


The "Map Table": The key piece needed to map columns between data sets

I set a goal to write a power query transform that was agnostic of specific column names and field counts, and so would not use Table.AddColumn, Table.RenameColumns, Table.RemoveColumns, or Table.ReorderColumns operations.

Mapping Strategy/Assumptions:

  • Data will not necessarily end up in the same column order between Source and Target.
  • Not all the columns map from Source to Target.
  • Not all the Target columns will be filled from the Source.

The solution: A "Map" table on an Excel sheet; A simple list of Source field names and Target Field names (I like using a column format for readability).


The Transforms

The "TblMap" Transform

The query reads the "Map" table data and flips it around so that the Source names are the table’s column names:


The complete M code used for this solution is shown here:


The "Output" Transform

This query references the tblMap transform and appends the original source data, giving something like this:


Now just promote the first row to Headers, overwriting the existing column names, and the new Target data structure is in place:


Dealing with un-mapped columns

But what about those pesky un-mapped columns (Column7 and Column8)? Normally I would use Table.RemoveColumns. I don't want to do that here, though, as this would hard code column names into the M code that might not exist next time, resulting in errors.

Instead, we just transpose the table and filter out any columns that begin with “Column”, and transpose it back.  The complete M code for the query is shown here:


And here is the output in Excel once we load it to a table:


Closing Thoughts

So there you go. One of the best things I like about this approach is how flexibly it can be modified. Spell “Klinger” wrong? Just modify the spelling in the Map table. Forget to add Rizzo or Nurse Able to the Target? Just add them to the table on the Target side and they are in the result. Forgot to include Dino in the Source data? Just add him to the list.

The sample file is attached. Give it a try. Hope it can be useful.

Column Name Translate

A thought on Data Types

I have not done a lot of testing with data types on this approach. My work will not do any math on the contents until after the re-mapping (I hope), so data typing can be done at the end. If there is any math to be done in the middle of the process, you would need to be careful not to have power Query treat numbers as integers (this has bitten me before).


The last step where extra column names are removed uses a transpose which could be really slow for long data sets. Another solution that could fix this would be to create a list from the Map table to automate a RemoveOtherColumns function.


Pass Parameters to SQL Queries

One of the questions I get quite frequently is how we can pass parameters to SQL queries, allowing us to make them dynamic. Someone asked a question in the forum on the topic, so that finally inspired me to write it up.

Before you do this…

There are a lot of reasons that you should NOT go this route.

Power Query is designed to take advantage of query folding when targeted against a database.  While this isn’t technically correct, you can look at query folding like this… As you connect to the database and start filtering and grouping via the user interface, Power Query passes these commands to the database to execute.  This means that the majority of the heavy lifting is done at the database, not your workstation.  This continues to occur until you hit a command that the database doesn’t know, at which point it returns the data to Power Query, and the rest is done in your instance of Excel.

Why is this an issue?  Dynamic parameters use custom lines of code, which can’t be folder.  In the case of the poster’s question, this means that he just asked to bring 40 million records into Excel, rather than filtering them down on the server.  Take a guess as to which one is faster?

But what if I want to Pass Parameters to SQL Queries dynamically?

Listen, I totally get it.  I love dynamic queries too.  And anyone who knows me is aware that I’m super obsessed with making my data tables as short and narrow as possible.  This almost always involves filtering based on parameters that the user needs to pass at run time.  So are we dead in the water?  No, not by a long shot.

How to Pass Parameters to SQL Queries – Method 1

I’m a big fan of query folding, and would encourage you to use it wherever possible.  In order to do that, you should use the user interface to connect to the database and drive as many filter, sort and group by operations as you possibly can.  The goal is to push as much work to the server as possible, resulting in the narrowest and shortest data table that you can accomplish.  Once you have that, land it in a Connection Only query.  And from there use your dynamic parameters to filter it down further to get just what you need.

I have no idea what was in the 40 million row data set that the user was working with, but let’s assume it was 40 years of data related to 4 divisions and 30 departments.  Assume that our user (let’s call him Mark) wants to bring in the last 2 years data, is focussing only on the Pacific division, and wants to give the user choice over which department they need to work with.  For ease of assumption, we’ll assume that each year is 1/40 of the annual record load and each division provides 1/4 of the total records.  (Yes, I’m aware that nothing is that easy… this is an illustration of concept only!)

The recommended steps would be to do this:

  • Create the Staging query
    • Connect to the raw database table
    • Filter to only the Pacific Division – Server reduces 40m to 10m records
    • Filter to only the 2 years of data – Server reduces 10m to 500k records (10/40*2)
    • Land this output into a staging query – 500k records total
  • Create the parameter table and the fnGetParameter query
  • Create a query that references the Staging query and filters the department to the one pulled via the fnGetParameter query

That should take as much advantage as possible, and means that Power Query only needs to run the processing of 500k records against our dynamic criteria.

Where Method 1 breaks down

But what if the data set is still too big?  What if you need to parameterize the Division, the Date Range and the Department?  In order to avoid issues from the formula firewall, you would have to do this:

  • Create the Staging query
    • Connect to the raw database table
  • Create the parameter table and the fnGetParameter query
  • Create a query that references the Staging query and…
    • Collects the Division, Date and Department variables
    • Filters to only the Pacific Division
    • Filters to only the 2 years of data
    • Filters to only the selected department

Seems about the same, doesn’t it?  Except that this time we can’t take advantage of query folding.  To pass a parameter to the database, we have to separate it from the parameters in order to avoid the formula firewall.  This means that we break query folding.  And this means that Power Query needs to pull in all 40 million records, and process them.  Not the server, your Excel instance.

I don’t know how much RAM you have (and don’t care unless you’re on 64 bit), or how many processor cores you have (as Power Query is single threaded), you’re in for a LOOONNNGGG wait… if it doesn’t just tip over on you.

So how do we fully parameterize this stuff?

How to Pass Parameters to SQL Queries – Method 2

The good news that it can be done, the bad news is that you need:

  1. SQL Skills, and
  2. An adjustment to the default Power Query load behaviour

Let’s talk SQL Skills

The reason you need SQL skills is that you need to be able to write the most efficient query you possibly can, and pass this into the query when you connect to the database. (Thos italics, as you’ll see, are key.)  So, let’s assume that I want to connect to the old AdventureWorks database and pull records from the Sales.SalesOrderHeader table where CustomerID = 29825.  You need to be able to write this:

SELECT * FROM Sales.SalesOrderHeader WHERE CustomerID='29825'

Why?  Because you need to include that query when you’re building/testing your code.  It goes in the advanced options, below:


(You may need to trust the Native Database Query to get to the next step.)

So that created the following code for me:

Source = Sql.Database("", "AdventureWorks2012", [Query="SELECT * FROM Sales.SalesOrderHeader WHERE CustomerID='29825'"])

Modifying the hard coded query to use dynamic parameters

I then set about fully parameterizing my query using the fnGetParameter query detailed here, and the table shown below:


Here’s the code I cobbled together to do this:

//Pull in a values from the parameter table
dbURL = fnGetParameter("Database URL"),
dbName = fnGetParameter("Database Name"),
dbTable = fnGetParameter("Database Table"),
sFilterField = fnGetParameter("Filter Field"),
sFieldValue = Text.From(fnGetParameter("Field Value")),

//Create the query
dbQuery = "Select * FROM " & dbTable & " WHERE " & sFilterField & "='" & sFieldValue & "'",

//Get the data
Source = Sql.Database(dbURL,dbName,[Query=dbQuery])


I won’t go through the fnGetParameter function, as it’s quite well detailed in the blog post, but the key to understand here is that we are pulling a variety of items from the worksheet table, and putting them all together to feed the line starting with dbQuery.  This line dynamically sources the database path, database name and the SQL query.  Wouldn’t this be heaven if it worked?

Here comes the Formula Firewall again…

But no:


Now if that’s not enough to make you scream… and here’s the issue…

What I really wanted to do was create a power query that connects to the database without declaring the SQL query up front.  Something like this:

Source = Sql.Database("", "AdventureWorks2012")

My thought is that I could load this as a connection only query, then reference it and add the dynamic query afterwards.  Unfortunately, I got nowhere.  I’m not saying it can’t be done, but I couldn’t figure this out.  It seems that the only way to pass a query to the database is to pass it during the initial connection.  But doing so, by its very nature, violates the formula firewall.

So how can we get past it?

Bypassing the Formula Firewall

Yes, we can make this work.  But doing so involves turning off Privacy settings.  I’m not generally a big fan of turning off firewalls, but this one just aggravates me to no end. Normally we turn this off to avoid prompting messages.  In this case it just flat out prevents us from running.  So let’s kill it:

  • Go to Query Settings –> Privacy
  • Select Ignore the Privacy Levels and potentially improve performance

And at this point you’ll find out that it works beautifully… for you.  You’ll most likely need to have anyone else who uses the file set the above option as well.

Security Settings

The security setting we changed above is workbook specific.  Now I’m not recommending you do this, but if you get tired of the privacy settings overall, you can turn them off for all workbooks in the Query Options –> Security tab.  The second arrow is pointing at the relevant option:


And how about that?  Check out the first option… that one lets you avoid prompting about Native Database Queries.  (I seriously have to question why a SELECT query should trip a warning.)

Sample Workbook

Yes, I’ve got one, which you can download here, but it comes with a catch…

I’ve set it up to talk to a SQL Server in order to demo this, as it’s the big databases with query folding that cause us this issue.  You might notice that not too many people provide free access to a SQL server since they cost money to run.  For this reason, you need a login and password to refresh the solution and really see it work.

As it happens, if you’ve bought a copy of M is for Data Monkey, or attended our PowerQuery.Training workshop, then you’ve already got it the credentials. (They are on page 66 of the book.)  And if you haven’t… what are you waiting for?  🙂

We need your votes!

Hey everyone, we need your votes to make a difference in Power Query and Power Pivot!  There are a couple of items in the uservoice forums that I’d like to bring your attention to, and hopefully entice you to vote them up.  The more votes we get, the easier it is for the program managers in the design teams to get the support to actually implement these features.  They ARE interested, they just need you to up-vote them to get them done.

Where we need your votes:

#1 - Add Intellisense to the M Editor

So the idea here is simple: Add Intellisense and better general editing capabilities in the Advanced Editor.  This would make a huge difference to those of us writing M code, and I’ve also suggested in the comments that this be extended to the Add Custom Column dialog.

What kills me on this is the signature of the original submitter:  “Software Engineer, Power BI Desktop”.  I don’t think I’ve ever seen a clearer case where they need our help to justify the budget to get this done.  Please go there and throw some votes on this.

Vote up the “Add Intellisense to the M Editor” idea.

#2 – Modification of the Power Pivot Field List experience

Back in November I posted a suggestion to improve the Pivot Table experience  which would benefit everyone, but especially Power Pivot users.  Full details of my suggestion can be found on the blog here, but the basic summary is this:  Allow the fields area to be collapsible in side by side view. This would make it WAY easier to rearrange fields by reducing unused whitespace.

I was really encourage to see Ashvini Sharma’s response which, paraphrased, says: “We want to do this too, so please get enough votes to help us justify it!”

Vote up the “Ability to collapse PivotTable field areas” idea.

My Ask To You

Please, take some time to throw some votes on these ideas, and encourage every other user you know to do the same.  It’s super easy to do, just go there, click the Vote button, assign as many as you want and verify you’re real with your email address.  (The only email I’ve ever received from this is when they confirmed a feature got implemented.)

Again, we need your votes.  Help us out!  I’d like to see both of these hit 500 votes in order to give Microsoft the justification they need to get these done.