The Definitive Guide to DAX, Third Edition

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Errata corrige

To ensure the ongoing accuracy of this book and its companion content, we have reviewed and confirmed the errors listed below. If you find a new oversight not included in both of the following sections, please report it to us.

Important issues

Corrections in this section are important to fully understand the concepts explained in the book.

Page 476: Year is a bound column

In the paragraph after Figure 12-21, the description mention Year as an unbound column, while it is a bound column. The right sentence is:

The source table now contains three columns: Continent and Year are bound, whereas @Sales is unbound.

Feb 3, 2026

Minor issues

Corrections in this section do not affect the ability to learn the concepts explained in the book.

Page 19: SUMX instead of SUM
The measure defined in the second line of the first code snipped should be SUMX instead of SUM. The correct first two lines are as follows:
```
DEFINE
    MEASURE Sales[Sales Amount] = SUMX ( Sales, Sales[Quantity] * Sales[Net Price] )
```
Dec 20, 2025
Page 39: Gross Margin Pct should reference Sales[LineMargin]
The measure preceding Figure 2-7 should reference Sales[LineMargin] instead of Sales[GrossMargin].
The definition of Gross Margin Pct should be the following:

Measure in Sales table
```
Gross Margin Pct = SUM ( Sales[LineMargin] ) / SUM ( Sales[LineAmount] )
```
Jan 20, 2026
Page 57: Inaccurate calculation in the Occurrences measure
The implementation of the # Occurrences measure counts the number of keywords, not the number of products that contain at least one of the keywords mentioned.

A correct version of the calculation is the following:
```
# Occurrences = 
COUNTROWS (
    FILTER (
        'Product',
        COUNTROWS (
            FILTER ( 
                Keywords,
                CONTAINSSTRING ( 'Product'[Product Name], Keywords[Keyword] )
            )
        ) > 0
    )
)
```
The only difference in the result is the Total, which is 900 instead of 943 for # Occurrences and 35.76% instead of 37.47% for Perc.

However, for the purpose of this initial introduction, this is a minor issue. The goal was to expose the syntax of two nested iterations that will be explained later in the book.

Jan 2, 2026
Page 61: Figure 2-20 description

The description in Figure 2-20 should reference “category” instead of “brand”. The correct description of Figure 2-20 is the following:

RELATEDTABLE returns all the products for each category.

Mar 2, 2026
Page 83: Figure 3-3 marker 2 should be close to 2018

The marker (2) in Figure 3-3 is close to “Female”, but it should be close to “2018” on the highlighted row.

Jan 23, 2026
Page 128: Sum instead of average

In the first paragraph of the page, immediately before Figure 4-15, the noun “average” should be “sum” in the second sentence, which should be read as follows:

Therefore, the value computed is the sum of all brands in the given year, …

Jan 8, 2026
Page 144: Measure for icon result

In the first paragraph of “Computing the icon” section, the result of the measure for the icon is -1, 0, or 1 instead of “1 or 2. Therefore, instead of:

We write a measure that returns 1 or 2 based on the sign…

The right sentence should be:

We write a measure that returns -1, 0, 0r 1 based on the sign…

Feb 3, 2026
Page 168: Figure 5-5 label correction

The Figure 5-5 label should say “two ore more products” instead of “more than two products”. The correct label is:
FIGURE 5-5 # Good Customers shows the customers who bought two or more products.

Jan 4, 2026
Page 172: Net Price should be Unit Price column reference in code snippet
The code snippet iterates Product[Net Price] instead of Product[Unit Price]. The right code snippet should be as follows:
```
SUMX (
    VALUES ( 'Product'[Unit Price] ),
    IF (
        'Product'[Unit Price] >= 10,
        'Product'[Unit Price] * [Sales Amount]
    )
)
```
Jan 4, 2026

Page 174: Remove Sales[Quantity] from Amount variable assignment expression

The Amount variable in the code snippet should be assigned to Sales[Net Price] without being multiplied by Sales[Quantity].
The right code snippet is the following:

Avg Amt per Kg =
AVERAGEX (
    Sales,
    VAR Amount = Sales[Net Price]
    VAR NormalizedWeight =
        SWITCH (
            RELATED ( 'Product'[Weight Unit Measure] ),
            "ounces", 0.0283495,
            "grams", 0.001,
            "pounds", 0.453592
        ) * RELATED ( 'Product'[Weight] )
    VAR Result = DIVIDE ( Amount, NormalizedWeight )
    RETURN
        Result
)

Jan 13, 2026

Page 182: Use ‘Product'[FirstSale] instead of ‘Product'[First Sale]

In the third line of the code snipped for the measure in the Sales table, use ‘Product'[FirstSale] instead of ‘Product'[First Sale]. The right code is as follows:

First Week Sales = 
SUMX (
    VALUES ( 'Product'[FirstSale] ),
    VAR FirstSale = 'Product'[FirstSale]
    RETURN
        CALCULATE (
            [Sales Amount],
            Sales[Order Date] >= FirstSale 
                && Sales[Order Date] < FirstSale + 7
        )
)

Jan 27, 2026

Page 187: Missing comma after RELATEDTABLE ( Sales )

There is a missing comma at the end of RELATEDTABLE ( Sales ) on the sixth row of the code example.

SUMX (
    'Product Category',                   -- Scans the Product Category table
    SUMX (                                -- For each category
        RELATEDTABLE ( 'Product' ),       -- Scans the products
        SUMX (                            -- For each product
            RELATEDTABLE ( Sales ),       -- Scans the sales of that product
            Sales[Quantity]               --
                * 'Product'[Unit Price]   -- Computes the sales amount of that sale
                * 'Product Category'[Discount]
        )
    )
)

Jan 27, 2026

Page 226: SUMMARIZECOLUMNS instead of ADDCOLUMNS and SUMMARIZE

In the first paragraph of the “Computing the best store by product” section, use SUMMARIZECOLUMNS instead of “ADDCOLUMNS and SUMMARIZE working together”.
The right sentence is:

[…] let us look at an example of SUMMARIZECOLUMNS to solve a non-trivial scenario. […]

Feb 3, 2026
Page 230: Use Product[Brand] instead of Product[Color] after Figure 6-26

In the paragraph after Figure 6-26, use Product[Brand] as a column reference instead of Product[Color]. The right sentence should be:

The Brand Name measure uses COUNTROWS to check whether Product[Brand] has only one value visible in the current filter context.

Jan 26, 2026
Page 235: Remove “expanded” from “of the same expanded table” sentence.

In the last sentence of the page, just before the Conclusions section of Chapter 6, the word “expanded” must be eliminated from “of the same expanded table,” resulting in “of the same table”. The right sentence is:

ALLSELECTED proves particularly useful. You can use as arguments of ALLSELECTED a table or a list of columns of the same table, or no parameters at all.

Jan 28, 2026
Page 240: Remove ‘)’ after Sales[CustomerKey]
In both code snippets of the page (first two code snippets of “The importance of variable names” section), there is a bracket ‘)’ after Sales[CustomerKey] that should be removed.

Instead of:
```
        Sales[CustomerKey] ),
```
The code should be:
```
        Sales[CustomerKey],
```
Feb 3, 2026
Page 256: Figure 8-1 filters Product[Color] instead of Sales[Net Price]
In Figure 8-1, the filter is on Product[Color] instead of Sales[Net Price].
The correct DAX Code is the following:
```
CALCULATE (
    [Sales Amount],
    'Product'[Color] = "Red"
)
```
Feb 5, 2026
Page 270: Typo in Figure 8-14

The Row result or “Row 2” in Figure 8-14 should be 54.95 instead of 57.95.

Feb 7, 2026
Page 281: Outer row context instead of outer filter context before Figure 8-20

In the last paragraph of the page, the one preceding Figure 8-20 in the following page, the reference to the “outer filter context” should be to the “outer row context”. The correct sentence is:

[…] the value of Date[Year] is taken from the outer row context […]

Jan 30, 2026
Page 289: Clarification about context transition

At the end of the second paragraph in the section “Leveraging context transition in iterators” (which is the last sentence at page 289), the reference to the algorithm without context transition is inaccurate, because RELATEDTABLE internally is a CALCULATETABLE that works with a context transition. The following sentence:

We will first show the algorithm without using the context transition and then make it better by leveraging the context transition.

Should be rephrased as follows:

We will first show the algorithm using table stored in a variable and then make it better by leveraging the context transition.

Feb 7, 2026
Page 297: CROSSFILTER instead of USERELATIONSHIP

In the paragraph before Figure 8-28, instead of USERELATIONSHIP, the function should be CROSSFILTER (as correctly stated in the following paragraphs). The correct sentence is:

Despite the model’s unidirectional relationship between Product and Sales, as shown in Figure 8-28, USERELATIONSHIP can change the cross-filter direction and make it bidirectional.

Jan 24, 2026
Page 308: Use Sales[Net Price] instead of Sales[Unit Cost]
The two calculated columns MarginPct and Margin should reference Sales[Net Price] instead of Sales[Unit Cost].

The right definition is as follows:

Calculated columns in Sales table
```
MarginPct = DIVIDE ( Sales[Margin], Sales[Net Price] )

Margin = Sales[MarginPct] * Sales[Net Price]
```
Feb 16, 2026

Page 376: Parameter name mismatch in RangeLookup function

The parameters used in the function RangeLookup have name different from the parameters: colMin, colMax, and colTarget should be minColumn, maxColumn, and targetColumn, respectively.
The correct complete definition is the following:

Function definition

RangeLookup = (
    search : SCALAR VAL,
    lookupTable : ANYREF EXPR,
    minColumn : ANYREF EXPR,
    maxColumn : ANYREF EXPR,
    targetColumn : ANYREF EXPR
) =>
    SELECTCOLUMNS (
        FILTER (
            lookupTable,
            minColumn <= search && maxColumn > search
        ),
        "@Result", targetColumn 
    )

Feb 7, 2026

Page 433: CROSS APPLY instead of OUTER APPLY

In the first sentence of the “Using GENERATE and GENERATEALL” section, the reference to OUTER APPLY should be replaced by CROSS APPLY, which describes the logic of GENERATE, while OUTER APPLY describes the logic of GENERATEALL. A better version of the first sentence is the following one:

GENERATE is a powerful function that implements the ~~OUTER APPLY~~ CROSS APPLY logic from the SQL language, while GENERATEALL implements the OUTER APPLY logic.

Feb 4, 2026
Page 470: Customer[Name] instead of Sales[Order Date]

In the paragraph before Figure 12-16, the column reference to Sales[Order Date] should be to Customer[Name]. The right sentence is:

OFFSET creates its source table using SUMMARIZE, which returns Customer[Name] and Sales[Order Number].

Feb 3, 2026
Page 471: Incorrect table headers in Figure 12-17

The Sales and Product table headers in Figure 12-17 should be removed from the figure, they are unrelated to the content displayed.

Nov 25, 2025
Page 487: Reference to SUMX instead of CALCULATE

The first paragraph on the page, immediately after Figure 12-31 in the previous page, has a reference to SUMX that is not present in the code executed for Figure 12-31.

At the beginning of the paragraph, instead of:

This behavior occurs because the context transition executed by SUMX while iterating over the
result of WINDOW is not overriding the outer filter context generated by SUMMARIZECOLUMNS.

The correct sentence should be the following:

This behavior occurs because the filter context applied by CALCULATE with WINDOW does not override the filter context generated by SUMMARIZECOLUMNS.

Feb 3, 2026
Page 491: Missing assignment operator in DAX measure
There is a missing “=” assignment operator after the line VAR Result in the 6 Months Avg measure. The correct code of the final part of the 6 Months Avg measure should be:
```
VAR Result =
    IF (
        [Sales Amount] > 0,
        MovingAverage
    )
RETURN Result
```
Nov 25, 2025
Page 502: PARTITIONBY instead of ORDERBY in last sentence

In the last sentence of the last paragraph, which is the paragraph after prevExchange 2 calculated column definition, the function ORDERBY should be PARTITIONBY. The correct sentence is:

Two are specified in the PARTITIONBY section, and the third is specified in the
MATCHBY section.

Feb 3, 2026
Page 515: In Figure 13-2, year is 2018

The filter for Date[Year] in Figure 13-2 should be 2018 instead of 2017 for both “Cell filter context” and “Active filters”.

Mar 1, 2026
Page 522: DateTime instead of DateType

In the third bullet point of “Building a date” table section, there is a reference to DateType that should be DateTime. The correct sentence is:

[…] (even though the physical column internally remains of type DateType). […]

Feb 3, 2026
Page 556: DATESINPERIOD instead of PARALLELPERIOD

In the first line of the last paragraph of the page (before Figure 13-30), the sentence should reference DATESINPERIOD instead of PARALLELPERIOD.
The right version is: “The second argument of DATESINPERIOD is the reference date, …”

Jan 7, 2026
Page 568: Comparison in FirstDateWithTransactions function
The FirstDateWithTransactions function defined in the “TMLD definition for function” snippet should use “>=” instead of “<=” as a comparison between dateColumn and FirstVisibleDate. The right assignment of the FirstDateWithData variable is the following:
```
VAR FirstDateWithData =
    CALCULATE (
    MIN ( dateTransaction ),
    KEEPFILTERS ( dateColumn <= FirstVisibleDate )
)
```
Feb 18, 2026
Page 608: Internal note to ignore in Figure 14-38

The note ** insert F14xx38 no crop on the top of Figure 14-38 should be ignored, it is an internal editing note that was left in production by mistake.

Jan 9, 2026
Page 619: Figure 14-50 description

The correct description for Figure 14-50 should be the following:

Figure 14-50 The Monthly Moving Average computes the average of the full month also at the day level.

Feb 3, 2026

Page 684: Use ISINSCOPE instead of ISFILTERED

The definition of the ParentChild calculation item should use ISINSCOPE instead of ISFILTERED. The correct code is the following:

Calculation group

CALCULATIONGROUP ParentChild[Hide unwanted rows]

    CALCULATIONITEM "ParentChild" =
        VAR BrowseDepth =
            ISINSCOPE (Persons[Level1]) +
            ISINSCOPE (Persons[Level2]) +
            ISINSCOPE (Persons[Level3])
        VAR MaxDepth = MAX ( Persons[NodeDepth] )
        VAR Result =
            IF (
                MaxDepth >= BrowseDepth,
                SELECTEDMEASURE ()
            )
        RETURN
            Result

Feb 3, 2026

Page 717: Year column in Figure 18-1

The table SalesDeliveryDate in Figure 18-1 should have 2018 instead of 2017 in the second and third row of the column Year (the year should correspond to the Date column).

Feb 22, 2026
Page 741: Figure 18-18 description

The description for Figure 18-18 references Date instead of Product. The correct description is the following:

FIGURE 18-18 When the bidirectional cross-filter is enabled between Sales and Product, the filter will now propagate from Customer to Product.

Feb 3, 2026
Page 746: Typo in Rec Amt CF REMOVEFILTERS measure name

In the first line of the paragraph before Figure 18-25, the measure referenced should be Rec Amt REMOVEFILTERS instead of Rec Amt CF REMOVEFILTERS. The right start of the paragraph is:

In the other measure, Rec Amt REMOVEFILTERS, we have a version […]

Feb 3, 2026
Page 764: Date instead of MonthlyBudget in one reference

The last paragraph of the page include a sentence with a reference to MonthlyBudget that should be Date. Here is the complete sentence, with the correction shown after the struck-through MonthlyBudget reference.

[..] MonthlyBudget depends on the presence of a blank row because it uses column values from ~~MonthlyBudget~~ Date, and BLANK is one of the many possible values. […]

Feb 3, 2026
Page 768: Categories instead of brand

The last sentence in the paragraph before Figure 19-6 references “brands” instead of “categories”. Here is the complete sentence, with the correction shown after the struck-through brands reference:

Summing the ~~brands~~ categories in Canada would produce a budget much larger than the total displayed for Canada.

Feb 3, 2026

Page 794: Code in the book not aligned to the code in the sample file

The code of the Open Stores Amount 2 measure is inaccurate, the definition of the AllStoreStatuses variable does not include the correct column @OpenYears filtered in OpenStores; the sample file contains the correct code, which is the following:

Measure in Sales table

Open Stores Amount 2 = 
VAR AllSelectedYears =
    CALCULATETABLE ( 
        SUMMARIZECOLUMNS ( 'Date'[Year], "@", COUNTROWS ( StoreStatus ) ), 
        ALLSELECTED ( 'Date' ),
        ALLSELECTED ( 'Product' ),
        ALLSELECTED ( Store )
    )
VAR NumberOfYears = 
    COUNTROWS ( AllSelectedYears )
VAR AllStoreStatuses =
    SUMMARIZECOLUMNS (
        Store[StoreKey],
        'Product'[Category],
        "@OpenYears",
            CALCULATE (
                COUNTROWS ( StoreStatus ),
                ALLSELECTED ( 'Date' ),
                StoreStatus[Status] = "Open"
            )
    )
VAR OpenStores =
    SELECTCOLUMNS (
        FILTER ( AllStoreStatuses, [@OpenYears] == NumberOfYears ),
        Store[StoreKey],
        'Product'[Category]
    )
VAR Result =
    CALCULATE ( [Sales Amount], KEEPFILTERS ( OpenStores ) )
RETURN
    Result

Jan 14, 2026