Data formats supported by Azure Data Explorer for ingestion

Data ingestion is the process by which data is added to a table and is made available for query in Azure Data Explorer. For all ingestion methods, other than ingest-from-query, the data must be in one of the supported formats. The following table lists and describes the formats that Azure Data Explorer supports for data ingestion.

Note

Before you ingest data, make sure that your data is properly formatted and defines the expected fields. We recommend using your preferred validator to confirm the format is valid. For example, you may find the following validators useful to check CSV or JSON files:

For more information about why ingestion might fail, see Ingestion failures and Ingestion error codes in Azure Data Explorer.

Format Extension Description
ApacheAvro .avro An AVRO format with support for logical types. The following compression codecs are supported: null, deflate, and snappy. Reader implementation of the apacheavro format is based on the official Apache Avro library.
Avro .avro A legacy implementation for AVRO format based on .NET library. The following compression codecs are supported: null, deflate (for snappy - use ApacheAvro data format).
CSV .csv A text file with comma-separated values (,). See RFC 4180: Common Format and MIME Type for Comma-Separated Values (CSV) Files.
JSON .json A text file with JSON objects delimited by \n or \r\n. See JSON Lines (JSONL).
MultiJSON .multijson A text file with a JSON array of property bags (each representing a record), or any number of property bags delimited by whitespace, \n or \r\n. Each property bag can be spread on multiple lines. This format is preferred over JSON, unless the data is non-property bags.
ORC .orc An ORC file.
Parquet .parquet A Parquet file.
PSV .psv A text file with pipe-separated values (|).
RAW .raw A text file whose entire contents is a single string value.
SCsv .scsv A text file with semicolon-separated values (;).
SOHsv .sohsv A text file with SOH-separated values. (SOH is ASCII codepoint 1; this format is used by Hive on HDInsight.)
TSV .tsv A text file with tab-separated values (\t).
TSVE .tsv A text file with tab-separated values (\t). A backslash character (\) is used for escaping.
TXT .txt A text file with lines delimited by \n. Empty lines are skipped.
W3CLOGFILE .log Web log file format standardized by the W3C.

Note

  • Ingestion from data storage systems that provide ACID functionality on top of regular Parquet format files (e.g. Apache Iceberg, Apache Hudi, Delta Lake) is not supported.
  • Schema-less Avro is not supported

Supported data compression formats

Blobs and files can be compressed through any of the following compression algorithms:

Compression Extension
GZip .gz
Zip .zip

Indicate compression by appending the extension to the name of the blob or file.

For example:

  • MyData.csv.zip indicates a blob or a file formatted as CSV, compressed with ZIP (archive or a single file)
  • MyData.json.gz indicates a blob or a file formatted as JSON, compressed with GZip.

Blob or file names that don't include the format extensions but just compression (for example, MyData.zip) is also supported. In this case, the file format must be specified as an ingestion property because it cannot be inferred.

Note

  • Some compression formats keep track of the original file extension as part of the compressed stream. This extension is generally ignored for determining the file format. If the file format can't be determined from the (compressed) blob or file name, it must be specified through the format ingestion property.
  • Not to be confused with internal (chunk level) compression codec used by Parquet, AVRO and ORC formats. Internal compression name is usually added to a file name before file format extension, for example: file1.gz.parquet, file1.snappy.avro, etc.

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