Identify considerations for relational data on Azure →mediumMultiple Choice

DP-900 Practice Question: Identify considerations for relational data on Azure

Exhibit

Refer to the exhibit.

```kusto
// KQL query in Azure Monitor
AzureDiagnostics
| where ResourceProvider == "MICROSOFT.SQL"
| where Category == "QueryStoreRuntimeStatistics"
| summarize avg_duration = avg(duration_s) by DatabaseName
| order by avg_duration desc
```

A DBA runs the following KQL query in Azure Monitor for an Azure SQL Database: `AzureDiagnostics | where Category == 'QueryStoreRuntimeStatistics'`. The query returns no results. What is the most likely reason?

⚠ Common exam trap

DP-900 often tests the assumption that a query returning no rows means a syntax or naming error, when the real cause is that the underlying data source feature (Query Store) was never enabled.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

Query Store is not enabled on the database

Query Store runtime statistics are only emitted to Azure Monitor's AzureDiagnostics table when Query Store is actually enabled on the database. If Query Store is off, no QueryStoreRuntimeStatistics records are generated, so the query legitimately returns zero rows even though the KQL syntax and category name are correct.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✓
Query Store is not enabled on the database
Why this is correct
Query Store is the SQL Server and Azure SQL Database feature that captures runtime query metrics such as CPU, duration, and execution counts. The QueryStoreRuntimeStatistics table is populated only when Query Store has been enabled for the database; if it has never been turned on, no rows are written to that table and the KQL query correctly returns an empty result set. Enable Query Store with ALTER DATABASE ... SET QUERY_STORE = ON to begin collecting this telemetry.
✗
The AzureDiagnostics table does not contain SQL data
Why it's wrong here
AzureDiagnostics is a consolidated table in Log Analytics that receives diagnostic data from multiple Azure services, including Azure SQL databases. When diagnostic settings are configured for an Azure SQL database to stream to Log Analytics, categories such as SQLInsights, AutomaticTuning, and QueryStoreRuntimeStatistics are written to this table. Therefore, the premise that SQL diagnostic data is absent from AzureDiagnostics is factually incorrect; the table is a valid destination for SQL telemetry.
✗
The category name is misspelled
Why it's wrong here
The category name used in the query, QueryStoreRuntimeStatistics, exactly matches the documented Log Analytics category for SQL Database query store runtime statistics. This category appears in the list of diagnostic categories that can be enabled for Azure SQL databases in the Azure portal. A misspelling would cause the query to return no data, but because the name is spelled correctly, that is not the reason for the empty result.
✗
The KQL syntax is incorrect
Why it's wrong here
The KQL query is syntactically well-formed: the where operator filters records based on a string comparison against the Category column, the project operator selects specific columns, and take limits the output to 10 rows. This is valid Kusto Query Language syntax that Azure Monitor accepts. If the syntax were invalid, Azure Monitor would return a parse error before attempting any data retrieval, not an empty result set.

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DP-900 Practice Question: Identify considerations for relational data on Azure

Exhibit

Why each option matters

Option-by-option breakdown

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