Explanation:

We are optimizing model1 in Fabric with two very large columns:
TransactionKey
Cardinality: 2.5 billion
Size: 160 GB
Description: surrogate key for SalesTransaction fact table.
SaleDateTime
Cardinality: 6.8 million
Size: 120 GB
Description: datetime (to the second) of when a sale occurred.
Goal:
Reduce model size.
Improve refresh performance (Import mode).
Ensure datetime values remain available .
Analysis per column
1. TransactionKey (very high cardinality)
Surrogate keys with extremely high cardinality do not add analytical value in a semantic model because they are not used in measures or grouping.
They take a lot of memory and reduce refresh performance.
Best practice: remove the column from the model.
2. SaleDateTime
Needed to analyze transactions by date and time.
However, storing the full datetime at second-level cardinality causes huge memory usage.
To optimize: split the column into Date and Time columns.
Reduces cardinality significantly.
Preserves full datetime information (can recombine if needed).
Improves compression and refresh speed.
TransactionKey: Remove the column.
SaleDateTime: Split the column.
References:
Microsoft Fabric optimization guidance - reduce cardinality
Best practices for datetime optimization in semantic models
# Answer Selection:
TransactionKey # Remove the column
SaleDateTime # Split the column

Explanation:
You should complete the code as follows:
Table
NativeQuery
EnableFolding
In Power Query, using Table before the SQL statement ensures that the result of the SQL query is treated as a table. NativeQuery allows a native database query to be passed through from Power Query to the source database. The EnableFolding option ensures that any subsequent transformations that can be folded will be sent back and executed at the source database (Microsoft SQL Server engine in this case).

To prevent new tables added to Lakehouse1 from being automatically added to the default semantic model, you should configure the semantic model settings. There should be an option within the settings of the semantic model to include or exclude new tables by default. By adjusting these settings, you can control the automatic inclusion of new tables.
References: The management of semantic models and their settings would be covered under the documentation for the semantic layer or modeling features of the Fabric tenant ' s lakehouse solution.

Explanation:

Step 1 - Read the Parquet file into a DataFrame
df = spark.read.parquet( " abfss://[email protected]/files/sales.parquet " ) This correctly loads the Parquet data into Spark.
Step 2 - Write into the Lakehouse as a managed table
If we want the result to be registered as a Lakehouse table and automatically appear in Lakehouse Explorer, we must:
Write the data in delta format (because Fabric Lakehouse tables are Delta tables ).
Save the table under the tables folder, not files .
So the correct code is:
df.write.mode( " overwrite " ). format ( " delta " ).saveAsTable( " tables/sales " ) Format: delta SaveAsTable Path: tables/sales References:
Lakehouse tables in Microsoft Fabric
Save DataFrame as Delta Table in Spark
# Answer Selection:
First dropdown # delta
Second dropdown # tables/sales

Explanation:

Comprehensive Detailed Explanation
From the case study:
Research division data for Productline2 is currently in CSV format in storage2.
Requirement: "All the Research division data in the lakehouses must be presented as managed tables in Lakehouse explorer." In Fabric lakehouses, managed tables are stored in Delta format inside the Tables folder.
Step 1: Reading the source
df = spark.read. format ( " csv " ) \
options(header= " true " , inferSchema= " true " ) \
load( " abfss://storage1.dfs.core.windows.net/files/productline2 " )
This correctly ingests the CSV source from ADLS Gen2.
Step 2: Writing to Lakehouse as a managed table
You must write the data in Delta format to ensure it is queryable and managed within the lakehouse.
The correct path is under Tables/ , because this is where Fabric automatically manages Lakehouse managed tables .
The target table should be named productline2 , so the correct path is:
df.write.mode( " overwrite " ). format ( " delta " ).save( " Tables/productline2 " ) Why not other options?
CSV or Parquet formats would not create a managed Lakehouse table; they would just create files.
Writing to productline2 directly (without Tables/ ) would store unmanaged files in the Lakehouse Files area, not managed tables.
Writing to Tables/research/productline2 adds an unnecessary subdirectory and is not the standard structure for managed tables.
Correct Final Code
df.write.mode( " overwrite " ). format ( " delta " ).save( " Tables/productline2 " ) References Managed tables in Microsoft Fabric Lakehouse Delta Lake support in Fabric Spark write to Lakehouse