DP-700: Implementing Data Engineering Solutions Using Microsoft Fabric

By Microsoft · Question Mode

QuestionQ65

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You have a KQL database that contains two tables named Stream and Reference. Stream contains streaming data in the following format.

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Reference contains reference data in the following format.

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Both tables contain millions of rows.

You have the following KQL queryset.

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You need to reduce how long it takes to run the KQL queryset.

Solution: Move the filter to line 02.

Does this achieve the goal?

Explanation

Filtering Stream by Temperature >= 10 before the inner join reduces the rows supplied to the join while preserving the result, because Temperature comes from Stream and the predicate does not rely on columns created by the join. Kusto guidance recommends placing filters immediately after table references to reduce the amount of data processed.

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