A SQL table-valued function that loads files in formats such as CSV, JSON, XML, Parquet, Avro, ORC, text or binary and infers their schema to return rows. Used with the STREAM keyword inside a streaming table, it relies on Auto Loader.
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Terms in this definition
- Serverless
Compute tier for single Azure SQL databases that scales automatically, pauses when idle and charges by the second. It is offered in General Purpose and Hyperscale, not Business Critical, and reserved capacity does not apply.
- TVF
Returns a table rather than one value. Written inline it holds only
RETURN (SELECT ...), acting like a view with parameters; Fabric warehouses and SQL analytics endpoints use such functions as predicates inside RLS policies. - Cluster Shared Volumes
Shared failover cluster storage that all nodes write to simultaneously, typically for Scale-Out File Server or Hyper-V. On SAN-backed storage, ReFS-formatted volumes work in redirected mode.
- JSON
Text-based format for structured data. ARM templates and Cosmos DB documents are written in it, and most Azure REST APIs exchange request and response bodies as application/json.
- XML
A text-based format for data, used for instance in message bodies.
- Parquet
Columnar file format, open source and aimed at analytics. Event Hubs Capture cannot produce it natively.
- Avro
An Apache file format that stores rows: a JSON header describes the layout, followed by record blocks held as binary. It compresses well, cutting storage needs and bandwidth.
- ORC
Optimized Row Columnar (ORC), an Apache column-oriented format that stores indexes and statistics inside the file. You can use it with Auto Loader and external tables but not with managed tables.