PL-300 Practice Test 9 — 10 Questions

Question 1

Refer to the exhibit. You are reviewing a Power Query script. The script fails with a 'DataSource.Error: Microsoft SQL: Login failed for user' error. Which step should you check first?

Accepted Answer

The credentials used in the Source step.. The error 'DataSource.Error: Microsoft SQL: Login failed for user' indicates an authentication failure when connecting to the SQL Server database. This occurs at the Source step, where Power Query first attempts to establish a connection using the provided credentials. Checking and correcting the credentials in the Source step is the logical first step because no subsequent data transformations (like removing columns, changing types, or filtering rows) can execute if the initial data source connection fails.

Answer

The column name in #"Removed Columns".

Answer

The data type transformation in #"Changed Type".

Answer

The filter condition in #"Filtered Rows".

Question 2

You have a column 'ProductID' that contains integers. You need to ensure that this column is used as a key in relationships. What data type should the column have?

Accepted Answer

Whole Number.. Option C is correct because in Power BI, relationship keys must be of a data type that supports exact matching and efficient indexing. Whole Number (integer) is the optimal type for primary keys in relationships, as it ensures unique, non-decimal values that Power BI can use for fast lookups and joins without precision issues.

Answer

Decimal Number.

Answer

Text.

Answer

Binary.

Question 3

Refer to the exhibit. You are reviewing a Power BI data source privacy configuration. The SalesSQL data source is set to 'Organizational' and the MarketingCSV is set to 'Private'. You plan to combine these two sources in a query. What will happen when the query is executed?

Accepted Answer

The query will succeed, but the combination may be blocked or data may be limited to protect the Private source.. Option C is correct because when combining an Organizational source with a Private source, Power BI restricts data propagation to protect the Private source. The Organizational data will be limited to what can be sent to the Private source, potentially causing performance degradation or blocking the combine operation. Option A is wrong because the combination is not entirely blocked, but limited. Option B is wrong because the Private level does not override the Organizational; instead, the most restrictive applicable rules apply. Option D is wrong because the combine is not allowed at full speed.

Answer

The query will succeed, but the MarketingCSV data will be treated as Organizational.

Answer

The query will succeed without any restrictions because the combine is allowed between Organizational and Private.

Answer

The query will fail with a privacy level error because the levels are incompatible.

Question 4

You are analyzing a Power BI dataset definition. The dataset refreshes but recently started failing with the error 'The 'OrderDate' column of the table 'Orders' has a date value that is out of range.' You need to diagnose the issue. What is the most likely cause?

Accepted Answer

The source table contains a date value that is not recognized as a valid DateTime by Power BI.. The error message indicates that a date value in the 'OrderDate' column of the 'Orders' table is out of the range supported by Power BI's DateTime type (1/1/1900 00:00:00 to 12/31/9999 23:59:59.999). This typically occurs when the source contains a date like '0001-01-01' or a future date beyond the upper bound, which Power BI cannot convert to a valid DateTime. Option A is correct because the source table has a date value that is not recognized as a valid DateTime by Power BI, causing the refresh to fail.

Answer

The columns in the dataset definition do not match the source table.

Answer

The connection string is invalid.

Answer

The M expression has a syntax error.

Question 5

You need to combine data from two tables in Power Query that have the same columns but different row sets. Which operation should you use?

Accepted Answer

Append Queries. Append Queries is the correct operation in Power Query when you need to combine two tables with identical columns but different row sets. It stacks the rows from the second table beneath the rows from the first table, effectively performing a union of the data. This is distinct from Merge Queries, which joins columns based on a key, and Group By, which aggregates data.

Answer

Union Queries

Answer

Group By

Answer

Merge Queries

Question 6

You have a table with a column 'Date' in text format (e.g., '2024-01-15'). You need to convert it to a date type. In Power Query, what is the best approach?

Accepted Answer

Change the column data type to Date in Power Query Editor.. Option C is correct because changing the data type in Power Query is the standard method. Option A is wrong because DAX calculated columns are for the data model, not for Power Query. Option B is wrong because Power Query can handle this natively. Option D is wrong because it is not necessary to split the column.

Answer

Split the column into year, month, day and then combine.

Answer

Use the Excel Power Query add-in.

Answer

Create a calculated column in DAX using DATEVALUE.

Question 7

You have a Power BI data model with a 'Sales' fact table and a 'Date' dimension. You need to create a calculated column in the 'Sales' table that shows the fiscal year based on a 'Date' column. The fiscal year starts on July 1. Which DAX expression should you use?

Accepted Answer

SWITCH(TRUE(), MONTH(Sales[Date]) >= 7, YEAR(Sales[Date]), YEAR(Sales[Date])-1). Option A is correct because it uses SWITCH with TRUE() to evaluate a logical condition: if the month of the date is July or later (MONTH >= 7), it returns the current year; otherwise, it returns the previous year. This correctly implements a fiscal year starting on July 1, as required.

Answer

YEAR(Sales[Date])

Answer

YEAR(Sales[Date]) + 1

Answer

FORMAT(Sales[Date], "YYYY")

Question 8

Which TWO of the following are valid data sources for Power Query in Power BI Desktop? (Select exactly two.)

Accepted Answer

SQL Server Analysis Services database. Option B is correct because Power Query in Power BI Desktop can connect directly to SQL Server Analysis Services (SSAS) databases using the Analysis Services connector, which supports both multidimensional and tabular models. This allows you to import or DirectQuery data from SSAS cubes or tabular models, leveraging MDX or DAX queries respectively.

Answer

SharePoint list

Answer

Power BI dataset

Answer

Microsoft Entra ID

Question 9

You are preparing data for a sales analysis report. The source system provides a table with columns: 'ProductID', 'ProductName', 'Category', 'SubCategory', 'Price', 'Cost'. You need to create a star schema. Which columns should be moved to dimension tables?

Accepted Answer

ProductID, ProductName, Category, and SubCategory. In a star schema, dimension tables contain descriptive attributes that provide context to measures. ProductID, ProductName, Category, and SubCategory are all descriptive attributes that should be moved to a dimension table (e.g., DimProduct) to reduce redundancy and enable efficient filtering and grouping. Measures like Price and Cost, however, are numeric values that typically belong in the fact table as additive or semi-additive measures.

Answer

ProductID and ProductName only

Answer

Price and Cost

Answer

ProductID, ProductName, Price, and Cost

Question 10

You are reviewing the M query above. The query connects to an Azure SQL database and filters orders after June 1, 2024. The query runs successfully in Power Query Editor, but when you close and apply, the data load fails. What is the most likely cause?

Accepted Answer

The database server is not accessible or credentials are missing.. The query runs successfully in Power Query Editor but fails during 'Close & Apply' because the editor uses a cached data preview, while the actual load requires a live connection to the Azure SQL database. The most likely cause is that the database server is inaccessible or the credentials are missing or expired at load time, which is a common connectivity issue in Power BI.

Answer

The date filter syntax is invalid.

Answer

The query has a syntax error in the let expression.

Answer

The column 'OrderDetails' does not exist.

PL-300 Practice Test 9 — 10 Questions

Exhibit

PL-300 Practice Test 9 — 10 Questions

Exhibit