Azure Data Explorer is correct.

This service is purpose built to ingest very large volumes of structured telemetry and access logs and to support fast, interactive, low latency queries over that data. It uses a columnar store and automatic indexing and it exposes a powerful query language that is optimized for ad hoc exploration and time series analysis which makes it suitable for massive log workloads.

Azure Data Lake Storage is not appropriate because it is designed for scalable file and object storage and batch analytics rather than for low latency interactive query and log exploration.

Azure Blob Storage is not appropriate because it provides general object storage without the built in query engine and indexing needed for fast, interactive analysis of structured log records.

Azure SQL Database is not appropriate because it is a relational database service that is not optimized for the very high ingest rates and the petabyte scale time series log queries that this scenario requires.

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