Apps Script V8 Runtime Is Here! What Does That Mean?

In February 2020, Google announced the launch of the V8 runtime for Apps Script, which is the same runtime environment that powers Chrome. It allows us to take advantage of all the modern JavaScript features.

A runtime environment is the engine that interprets your code and executes the instructions.

Historically, Apps Script used a runtime environment called Rhino, which locked Apps Script to an older version of JavaScript that excluded modern JavaScript features.

But no more!

In this guide, we’ll explore the basics of the new V8 runtime, highlighting the features relevant for beginner-to-intermediate level Apps Script users.

Enabling The Apps Script V8 Runtime

When you open the Apps Script editor, you’ll see a yellow notification bar at the top of your editor window prompting you to enable V8:

Enable V8 runtime in Apps Script

If you don’t see this notification, you can select Run > Enable new Apps Script runtime powered by V8

Enable V8 runtime in Apps Script

Save your script to complete the enabling process.

If you need to return to the old version (in the unlikely scenario your script isn’t compatible with the new V8 runtime) then you can switch back to the old Rhino runtime editor.

Select Run > Disable new Apps Script powered by V8.


New Logging In The Apps Script V8 Runtime

The new V8 runtime logger shows both the Logger.log and console.log results for the most recent execution under the View > Logs menu.

Previously the console results where only accessible via the Stackdriver Logging service.

Here’s an example showing the Logger and console syntax (notice Logger is capitalized and console is not, it matters):

function loggerExample() {
  Logger.log("Hello, world from Logger.log!");
  console.log("Hello, world from console.log!")
}

The output in our logger window (accessed via View > Logs) shows both of these results:

Logger and console logs in V8


Modern JavaScript Features

There are a lot of exciting new features available with modern JavaScript. They look strange at first but don’t panic!

There’s no need to start using them all immediately.

Just keep doing what you’re doing, writing your scripts and when you get a chance, try out one of the new features. See if you can incorporate it in your code and you’ll gradually find ways to use them.

Here are the new V8 features in a vague order of ascending difficulty:

Multi-line comments

We can now create multi-line strings more easily by using a back tick syntax:

// new V8 method
var newString = `This is how we do 
multi-line strings now.`;

This is the same syntax as template literals and it greatly simplifies creating multi-line strings.

Previously each string was restricted to a single line. To make multi-line comments we had to use a plus-sign to join them together.

// old method
var oldString = 'This is how we used\n'
+ 'to do multi-line strings.'; 

Default Parameters

The Apps Script V8 runtime lets us now specify default values for parameters in the function definition.

In this example, the function addNumbers simply logs the value of x + y.

If we don’t tell the function what the values of x and y are, it uses the defaults we’ve set (so x is 1 and y is 2).

function addNumbers(x = 1, y = 2) {
  console.log(x + y);
}

When we run this function, the result in the Logger is 3.

What’s happening is that the function assigns the default values to x and y since we don’t specify values for x and y anywhere else in the function.

let Keyword

The let statement declares a variable that operates locally within a block.

Consider this fragment of code, which uses the let keyword to define x and assign it the variable of 1. Inside the block, denoted by the curly brackets {…}, x is redefined and re-assigned to the value of 2.

let x = 1;
  
{
  let x = 2;
  console.log(x); // output of 2 in the logs
}
  
console.log(x); // output of 1 in the logs

The output of this in the logs is the values 2 and 1, because the second console.log is outside the block, so x has the value of 1.

Note, compare this with using the var keyword:

var x = 1;
  
{
  var x = 2;
  console.log(x); // output of 2 in the logs
}
  
console.log(x); // output of 2 in the logs

Both log results give the output of 2, because the value of x is reassigned to 2 and this applies outside the block because we’re using the var keyword. (Variables declared with var keyword in non-strict mode do not have block scope.)

const Keyword

The const keyword declares a variable, called a constant, whose value can’t be changed. Constants are block scoped like the let variable example above.

For example, this code:

const x = 1;
x = 2; 
console.log(x);

gives an error when we run it because we’re not allowed to reassign the value of a constant once it’s been declared:

const keyword error

Similarly, we can’t declare a const keyword without also assigning it a value. So this code:

const x;

also gives an error when we try to save our script file:

Apps Script V8 runtime const error message

Spread syntax

Suppose we have the following array of data:

var arr = [[1,2],[3.4],[5,6]];

It’s an array of arrays, so it’s exactly the format of the data we get from our Sheets when we use the getRange().getValues() method.

Sometimes we want to flatten arrays, so we can loop over all the elements. Well, in V8, we can use the spread operator (three dots … ), like so:

var flatArr = [].concat(...arr);

This results in a new array: [1,2,3,4,5,6]

Template Literals

Template literals are a way to embed expressions into strings to create more complex statements.

One example of template literals is to embed expressions within normal strings like this:

let firstName = 'Ben';
let lastName = 'Collins';
console.log(`Full name is ${firstName} ${lastName}`);

The logs show “Full name is Ben Collins”

In this case, we embed a placeholder between the back ticks, denoted by the dollar sign with curly brackets ${ some_variable }, which gets passed to the function for evaluation.

The multi-line strings described above are another example of template literals.

Arrow Functions

Arrow functions provide a compact way of writing functions.

Arrow Function Example 1

Here’s a very simple example:

const double = x => x * 2;

This expression creates a function called double, which takes an input x and returns x multiplied by 2.

This is functionally equivalent to the long-hand function:

function double(x) {
  return x * 2;
}

If we call either of these examples and pass in the value 10, we’ll get the answer 20 back.

Arrow Function Example 2

In the same vein, here’s another arrow function, this time a little more advanced.

Firstly, define an array of numbers from 1 to 10:

const arr = [1,2,3,4,5,6,7,8,9.10];

This arrow function will create a new array, called evenArr, consisting of only the even numbers.

const evenArr = arr.filter(el => (el % 2 === 0));
console.log(evenArr);

The filter only returns values that pass the conditional test: (el % 2 === 0) which translates as remainder is 0 when dividing by 2 i.e. the even numbers.

The output in the logs is [2,4,6,8]:

Apps Script V8 runtime arrow function logs

Other Advanced Features

There are more advanced features in V8 that are not covered in this post, including:

I’m still exploring them and will create resources for them in the future.


Migrating Scripts To Apps Script V8 Runtime

The majority of scripts should run in the new V8 runtime environment without any problems. In all likelihood, the only adjustment you’ll make is to enable the new V8 runtime in the first place.

However, there are some incompatibilities that may cause your script to fail or behave differently.

But for beginner to intermediate Apps Scripters, writing relatively simple scripts to automate workflows in G Suite, it’s unlikely that you’ll have any problems.

You can read more about migrating scripts to the V8 runtime and incompatibilities in the detailed documentation from Google.


Other Apps Script V8 Runtime Resources

V8 Runtime Overview

ES 6 Features for Google Apps Script: Template Literals

ES6 Features for Google Apps Script: Arrow Functions

Here’s a good explanation of the V8 runtime from Digital Inspiration

The new V8 runtime offers significant performance improvements over the old Rhino editor. Your code will run much, much faster! Here’s a deep dive: Benchmark: Loop for Array Processing using Google Apps Script with V8

Unpivot In Google Sheets With Formulas, Or How To Turn Wide Data Into Tall Data

Unpivot in Google Sheets is a method to turn “wide” tables into “tall” tables, which are more convenient for analysis.

Suppose we have a wide table like this:

Wide Data Table

We want to transform that data — unpivot it — into the tall format that is the way databases store data:

Unpviot in Google Sheets

But how do we unpivot our data like that?

It turns out it’s quite hard.

Much harder than going the other direction, pivoting tall data into wide data tables.

This article looks at how to do it using formulas, which is challenging and obtuse.

The formulas are complex and difficult to read so it’s hard to recommend this method in a production setting.

But it’s a fascinating look at advanced formulas in Google Sheets and I’m certain you’ll learn something new along the way.

If you need to do this in a production setting, then you might want to consider using the Apps Script code or example sheet from the first answer of this Stack Overflow post.

But if you’re ready for some complex formulas, let’s dive in…

Unpivot in Google Sheets – Solution 1

We’ll use the wide dataset shown in the first image at the top of this post, in Sheet1 of our Google Sheet.

Remember, what we’re trying to do is transform the wide data table into the tall data table. The output of our formulas should look like the second image in this post.

In other words, we need to create 16 rows to account for the different pairings of Customer and Product, e.g. Customer 1 + Product 1, Customer 1 + Product 2, etc. all the way up to Customer 4 + Product 4.

Of course, we’ll employ the Onion Method to understand these formulas.

Template

Click here to open the Unpivot in Google Sheets template

Feel free to make your own copy (File > Make a copy…).

(If you can’t open the file, it’s likely because your G Suite account prohibits opening files from external sources. Talk to your G Suite administrator or try opening the file in an incognito browser.)

Customers Column

To start, create a second Sheet and add a simple header row in row 1, with “Customer”, “Product” and “Value” in cells A1, B1 and C1 respectively.

Let’s create an array formula to populate the customers column. In cell A2, enter this:

=COUNTA(Sheet1!$1:$1)

This formula gives the count of the number of columns — 4 — in our wide dataset (assuming cell A1 in our original dataset is empty, per the first image of this post).

QUICK NOTE: when copy-pasting these formulas into your own Google Sheets, paste them directly into the formula bar to avoid any issues.

Similarly, this next formula would give the count of the number of rows — 3 — in our wide dataset (again assuming cell A1 in our original dataset is empty, per the first image of this post).

=COUNTA(Sheet1!$A:$A)

Multiplying these two together gives us the number of values in our table — 12 — which corresponds to the number of rows we’ll need in our new tall data table:

=COUNTA(Sheet1!$A:$A)*COUNTA(Sheet1!$1:$1)

So let’s create those 12 rows!

Wrap this with the SEQUENCE function, starting from 1:

=SEQUENCE(COUNTA(Sheet1!$A:$A)*COUNTA(Sheet1!$1:$1),1)

Now divide that by the count of rows:

=SEQUENCE(COUNTA(Sheet1!$A:$A)*COUNTA(Sheet1!$1:$1),1)/COUNTA(Sheet1!$A:$A)

Hmm, it gives an answer of 0.3333333 but we’ve lost our 12 rows…

…so turn it into an Array Formula silly!

=ArrayFormula(SEQUENCE(COUNTA(Sheet1!$A:$A)*COUNTA(Sheet1!$1:$1),1)/COUNTA(Sheet1!$A:$A))

Ah, that’s better. “But how does it help us?” I hear you ask.

Let’s round all those decimals up to the nearest integer, like so:

=ArrayFormula(ROUNDUP(SEQUENCE(COUNTA(Sheet1!$A:$A)*COUNTA(Sheet1!$1:$1),1)/COUNTA(Sheet1!$A:$A)))

Nice!

We now have the column vector 1,1,1,2,2,2,3,3,3,4,4,4 with repeating positions, which is exactly what we needed.

For the moment, leave this formula alone and let’s move to cell B2 to construct the next piece. We want to create a table of the column headings that we can “lookup” with those repeating positions. Don’t worry, it’ll make more sense in a moment!

Ok, so start with this formula in B2:

=ArrayFormula(COLUMN(Sheet1!$1:$1))

And try this formula in B3:

=ArrayFormula(Sheet1!$1:$1)

Can you see what we’re doing yet?

Let’s combine these in cell B2 as follows:

=ArrayFormula({COLUMN(Sheet1!$1:$1);Sheet1!$1:$1})

and delete the formula in cell B3.

The output should look the same, but it’s created with a single formula.

Now we can use the HLOOKUP function to lookup those positions into this data array we’ve created.

Change our formula in cell A2 to:

=ArrayFormula(HLOOKUP(ROUNDUP(SEQUENCE(COUNTA(Sheet1!$A:$A)*COUNTA(Sheet1!$1:$1),1)/COUNTA(Sheet1!$A:$A)),{COLUMN(Sheet1!$1:$1);Sheet1!$1:$1},2))

It’s nearly right, but the answer is offset slightly. Hmm.

Ah ok, it’s that blank cell in A1 of the original data that we didn’t account for. Our repeating positions really start from 2. It’s a simple fix to just add 1 to them.

=ArrayFormula(HLOOKUP(ROUNDUP(SEQUENCE(COUNTA(Sheet1!$A:$A)*COUNTA(Sheet1!$1:$1),1)/COUNTA(Sheet1!$A:$A))+1,{COLUMN(Sheet1!$1:$1);Sheet1!$1:$1},2))

That’s the customers populated in column 1.

What about the products in column 2?

Products Column

Well, it’s an almost identical formula, so I’ll just share it here and leave it to the reader to use the Onion Method to build it in steps.

Actually, no I won’t, that’s just me being lazy. Let’s walk through it together.

It’s a similar idea, but it looks a little different because we do a vertical lookup.

So, if you haven’t already, clear out cells B2 and B3.

Start with this SEQUENCE formula in cell B2:

=SEQUENCE(COUNTA(Sheet1!$A:$A)*COUNTA(Sheet1!$1:$1),1)

This time we want a sequence that looks like 1,2,3,1,2,3,1,2,3 etc. i.e. repeating. This calls for the MOD squad, I mean MOD function.

=MOD(SEQUENCE(COUNTA(Sheet1!$A:$A)*COUNTA(Sheet1!$1:$1),1),COUNTA(Sheet1!$A:$A))

Oops, make it an Array Formula:

=ArrayFormula(MOD(SEQUENCE(COUNTA(Sheet1!$A:$A)*COUNTA(Sheet1!$1:$1),1),COUNTA(Sheet1!$A:$A)))

Ah, that’s better. But it gives 1,2,0,1,2,0 etc. so it’s not quite right. Fix the ordering by subtracting 1 from the dividend of the MOD function:

=ArrayFormula(MOD(SEQUENCE(COUNTA(Sheet1!$A:$A)*COUNTA(Sheet1!$1:$1),1)-1,COUNTA(Sheet1!$A:$A)))

Now we have 0,1,2,0,1,2 etc.

Add 2 to this to get the repeating positions we want 2,3,4,2,3,4 (again, we start from 2 to account for the blank cell in A1 of our original dataset).

=ArrayFormula(MOD(SEQUENCE(COUNTA(Sheet1!$A:$A)*COUNTA(Sheet1!$1:$1),1)-1,COUNTA(Sheet1!$A:$A))+2)

Leave this formula sitting pretty for a moment, and begin a new one in cell C2. Build an array for the vertical lookup with this formula (feel free to build in steps, I’m jumping straight to the array version):

=ArrayFormula({ROW(Sheet1!$A:$A),Sheet1!$A:$A})

Now we can combine this into the formula in cell B2, using a VLOOKUP:

=ArrayFormula(VLOOKUP(MOD(SEQUENCE(COUNTA(Sheet1!$A:$A)*COUNTA(Sheet1!$1:$1),1)-1,COUNTA(Sheet1!$A:$A))+2,{ROW(Sheet1!$A:$A),Sheet1!$A:$A},2))

Woohoo!

There’s our products in repeating order and paired correctly with the customer column.

That leaves the values associated with each pair.

Values Column

Thankfully this is much simpler, using a standard INDEX / MATCH / MATCH construction to look up each pair.

The row offset in the INDEX function is found by matching the product with the product categories in column A of our original data, i.e.

=MATCH(B2,Sheet1!$A:$A,0)

The column offset is found by matching the customers, i.e.

=MATCH(A2,Sheet1!$1:$1,0)

Plug these both into the INDEX function:

=INDEX(Sheet1!$1:$1000,MATCH(B2,Sheet1!$A:$A,0),MATCH(A2,Sheet1!$1:$1,0))

which gives the value of 61 for the first pair, Customer 1 and Product 1.

Drag this formula down the column to fill in all the rows.

“Wait, what? Where’s the array formula? Can’t I just wrap this INDEX / MATCH / MATCH with an array formula wrapper?”

No bueno, I’m afraid.

The INDEX function does not play well with the Array Formula, so this option cannot be turned into an array formula.

Be patient, in solution 2 we’ll generalize this to use an array formula, but we have to approach it in a different, more verbose way.

Unpivot in Google Sheets – Alternative Solution 1

Since publishing this article, several readers pointed out an undocumented function called FLATTEN, available in Google Sheets. It’s perfect for this kind of computation.

The final formula to retrieve the values can be shortened to:

=FLATTEN(Sheet1!B2:E4)

where B2:B4 is the original, wide range.

Just be careful to line up the values with the correct customers and products, because this flatten function cycles through the four customers for each product and not the other way around.

I’ve added the full alternative solution into the template.

Unpivot in Google Sheets – Solution 2

Leaving the Customer and Product array formula columns well alone, let’s focus purely on the Values column.

We left solution 1 with a somewhat unsatisfactory INDEX / MATCH / MATCH formula for the values that, ahem, had to be dragged down the column — oh the horror! — because it wasn’t an array formula.

Gasp! We don’t like such manual work.

So let’s create an array formula to grab the values we need.

Think of the standard VLOOKUP:

=VLOOKUP( search_key, data, column_index, false )

The search_key is the repeating array 2,3,4,2,3,4,2,3,4 etc. created using the same formula construction as the first part of the Products formula from Solution 1.

The column_index is the repeating array 2,2,2,3,3,3,4,4,4, etc. created using the same formula construction as the first part of the Customers formula from Solution 1.

When you plug these into the VLOOKUP, you’re searching for 2 and returning column 2, then searching for 3 returning column 2, searching 4 returning column 2, then searching 2 returning column 3, etc.

In other words, traversing the array of values and grabbing each one in turn.

The data needs to be setup by adding a search column at the front, which is done using the curly brackets array literal construction, like so:

=ArrayFormula({ROW(Sheet1!$A$2:$A),Sheet1!$B$2:$1000})

All that’s left is to combine them into the VLOOKUP, like so:

=ArrayFormula(VLOOKUP(MOD(SEQUENCE(COUNTA(Sheet1!$A:$A)*COUNTA(Sheet1!$1:$1),1,2)-2,COUNTA(Sheet1!$A:$A))+2,{ROW(Sheet1!$A$2:$A),Sheet1!$B$2:$1000},ROUNDUP(SEQUENCE(COUNTA(Sheet1!$A:$A)*COUNTA(Sheet1!$1:$1),1)/COUNTA(Sheet1!$A:$A))+1))

Voila! Clear as mud, huh?

Unpivot in Google Sheets – Solution 3

In this solution, all we do is combine the three columns together into a single, giant array formula, using the curly bracket array literal construction.

Starting with the three columns combined:

= ArrayFormula({ Customer_Formula, Product_Formula, Values_Formula })

Next, we’ll wrap it with a QUERY function to remove null values:

= ArrayFormula( QUERY( { Customer_Formula, Product_Formula, Values_Formula } , "SELECT * WHERE Col3 IS NOT NULL" ))

The full array construction, with a static header row added, is:

=ArrayFormula( {"Customer","Product","Value";
QUERY( { Customer_Formula , Product_Formula , Values_Formula } , "SELECT * WHERE Col3 IS NOT NULL" )})

We can then simply plug in the Customer_Formula, Product_Formula and Values_Formula to create a one-stop shop for unpivoting our data:

=ArrayFormula({"Customer","Product","Value"; QUERY({HLOOKUP(ROUNDUP(SEQUENCE(COUNTA(Sheet1!$A:$A)*COUNTA(Sheet1!$1:$1),1)/COUNTA(Sheet1!$A:$A))+1,{COLUMN(Sheet1!$1:$1);Sheet1!$1:$1},2),
VLOOKUP(MOD(SEQUENCE(COUNTA(Sheet1!$A:$A)*COUNTA(Sheet1!$1:$1),1)-1,COUNTA(Sheet1!$A:$A))+2,{ROW(Sheet1!$A:$A),Sheet1!$A:$A},2),
VLOOKUP(MOD(SEQUENCE(COUNTA(Sheet1!$A:$A)*COUNTA(Sheet1!$1:$1),1,2)-2,COUNTA(Sheet1!$A:$A))+2,{ROW(Sheet1!$A$2:$A),Sheet1!$B$2:$1000},ROUNDUP(SEQUENCE(COUNTA(Sheet1!$A:$A)*COUNTA(Sheet1!$1:$1),1)/COUNTA(Sheet1!$A:$A))+1)
},"SELECT * WHERE Col3 IS NOT NULL")})

Unpivot in Google Sheets – Solution 4

This one really blew my mind when I first saw it and picked it apart.

Kudos to this person on Stack Overflow for the original amazing answer.

I’ve modified it slightly, but have merely contributed a minor update to an ingenious and original solution.

Here it is, in all it’s mysterious detail:

=ArrayFormula({"Customer","Product","Value";
QUERY(IFERROR(SPLIT(TRIM(TRANSPOSE(SPLIT(TRANSPOSE(QUERY(TRANSPOSE(QUERY(TRANSPOSE(IF(Sheet1!B2:Z<>"", Sheet1!A2:A&"🐠"&Sheet1!B1:1&"🐠"&Sheet1!B2:Z&"🌶", )), , 500000)), , 500000)),"🌶"))),"🐠"),""),"SELECT Col2, Col1, Col3 ORDER BY Col2 OFFSET 1",0)})

First off, what on earth are those fish 🐠 and chili peppers 🌶 doing in this formula? Is this some kind of joke?

No, no, my friend. Read on and you’ll find out!

But before we do that, let me show you the amazing trick with the QUERY function that is key to this formula.

Taking our dataset again:

Unpivot in Google Sheets wide table

Try this formula in cell H1:

=QUERY(A1:E4,"SELECT A",4)

See what it does?

Query headers trick

It joins the values in column A into a single string, because we’ve told the QUERY function to treat all 4 rows as headers. Crazy!

Even better, you can skip the SELECT statement altogether, like this:

=QUERY(A1:E4,,4)

which results in all of the columns being concatenated:

Query headers trick

Now that is interesting!

And it’s at the heart of how this crazy formula works.

Let’s build it up in steps, following the Onion Method.

The innermost IF function is (note the value_if_false argument is empty):

=ArrayFormula(IF(Sheet1!B2:Z<>"", Sheet1!A2:A&"🐠"&Sheet1!B1:1&"🐠"&Sheet1!B2:Z&"🌶", ))

which gives the following output:

Array If formula

For every row of data, the formula joins them such that each cell has a unique combination of product, customer and value.

Next we transpose this array and join using the funky QUERY-header row trick above:

=ArrayFormula(QUERY(TRANSPOSE(IF(Sheet1!B2:Z<>"", Sheet1!A2:A&"🐠"&Sheet1!B1:1&"🐠"&Sheet1!B2:Z&"🌶", )),,500000))

This gives a #REF! error, with the message “Result was not automatically expanded, please insert more columns (699).”

The array output is too wide for our current Sheet.

Wrap it with a transpose function to fix this and get all the data in a single column:

=ArrayFormula(TRANSPOSE(QUERY(TRANSPOSE(IF(Sheet1!B2:Z<>"", Sheet1!A2:A&"🐠"&Sheet1!B1:1&"🐠"&Sheet1!B2:Z&"🌶", )),,500000)))

Use a second QUERY function with this headers trick to bring these values together:

=ArrayFormula(TRANSPOSE(QUERY(TRANSPOSE(QUERY(TRANSPOSE(IF(Sheet1!B2:Z<>"", Sheet1!A2:A&"🐠"&Sheet1!B1:1&"🐠"&Sheet1!B2:Z&"🌶", )),,500000)),,500000)))

Now we basically just split this up based on the fish “🐠” and chili pepper “🌶” symbols that we used to separate the data packets.

Here’s the first split and transpose:

=ArrayFormula(TRANSPOSE(SPLIT(TRANSPOSE(QUERY(TRANSPOSE(QUERY(TRANSPOSE(IF(Sheet1!B2:Z<>"", Sheet1!A2:A&"🐠"&Sheet1!B1:1&"🐠"&Sheet1!B2:Z&"🌶", )),,500000)),,500000)),"🌶")))

By now, our data looks like this, which is getting closer:

Unpivot in Google Sheets

Use the TRIM function to fix those unsightly spacing issues.

Next, split it again across the tropical fish:

=ArrayFormula(SPLIT(TRIM(TRANSPOSE(SPLIT(TRANSPOSE(QUERY(TRANSPOSE(QUERY(TRANSPOSE(IF(Sheet1!B2:Z<>"", Sheet1!A2:A&"🐠"&Sheet1!B1:1&"🐠"&Sheet1!B2:Z&"🌶", )),,500000)),,500000)),"🌶"))),"🐠"))

Unpivot in Google Sheets

Nearly there now!

Remove the #VALUE! error with an IFERROR wrapper function. Use a QUERY wrapper to re-order the rows and columns as required. The OFFSET removes a blank row from showing up in the table. The formula now looks like this:

=ArrayFormula(QUERY(IFERROR(SPLIT(TRIM(TRANSPOSE(SPLIT(TRANSPOSE(QUERY(TRANSPOSE(QUERY(TRANSPOSE(IF(Sheet1!B2:Z<>"", Sheet1!A2:A&"🐠"&Sheet1!B1:1&"🐠"&Sheet1!B2:Z&"🌶", )),,500000)),,500000)),"🌶"))),"🐠"),""),"SELECT Col2, Col1, Col3 ORDER BY Col2 OFFSET 1"))

And the output like this:

Split function Google Sheets

The final step is borrowed from Solution 3 above, namely combining a static header row with array literals.

=ArrayFormula({"Customer","Product","Value"; MAIN_FORMULA })

Now we can insert our formula into this construction, in place of the MAIN_FORMULA placeholder:

=ArrayFormula({"Customer","Product","Value";
QUERY(IFERROR(SPLIT(TRIM(TRANSPOSE(SPLIT(TRANSPOSE(QUERY(TRANSPOSE(QUERY(TRANSPOSE(IF(Sheet1!B2:Z<>"", Sheet1!A2:A&"🐠"&Sheet1!B1:1&"🐠"&Sheet1!B2:Z&"🌶", )), , 500000)), , 500000)),"🌶"))),"🐠"),""),"SELECT Col2, Col1, Col3 ORDER BY Col2 OFFSET 1",0)})

Crazy formula in Google Sheets

Further Reading

For more information on the shape of datasets, have a read of Spreadsheet Thinking vs. Database Thinking.