could you please let us know the use of map drift in data preview tab and how it internally works, if pivot key always changing

@Neeraja

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Understanding Map Drift in Data Preview

Map Drift is a feature used in data processing tools to handle schema changes dynamically, especially when working with pivoted data. Here’s how it works and its significance:

Purpose of Map Drift:

• Dynamic Schema Handling: When your data source changes (like new product names being added), Map Drift allows you to adapt without needing to manually adjust your data pipeline.
• Data Integrity: It ensures that even if the pivot key (in your case, product names) changes, the data remains accurately mapped and aggregated.

How It Works Internally:

• Detection of Changes: The system monitors the incoming data for any changes in the schema, such as new or removed product names.
• Mapping Drifted Columns: When a change is detected, Map Drift automatically maps these new columns to the existing structure. For example, if a new product is introduced, it will create a new column for that product in the pivoted output.
• Aggregation: It continues to aggregate data (like summing profits) based on the updated pivot keys, ensuring that all relevant data is included.

Impact of Changing Pivot Keys:

• If the pivot key (product name) is frequently changing, Map Drift becomes essential. It allows the data preview to reflect the most current structure without manual intervention.
• This adaptability is crucial for maintaining accurate reporting and analysis, especially in dynamic environments where product offerings can frequently change.

Example Scenario

In your setup:

• Source: Product, Profit, Region
• Group By: Region
• Pivot Key: Product Name
• Pivoted Columns: Sum(Profit)

If a new product is added, Map Drift will automatically create a new column for that product in the pivoted output, ensuring that the sum of profits is accurately calculated for all products, including the new one.

Hope this helps. Do let us know if you any further queries.

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