JSON SerDe libraries

In Athena, you can use SerDe libraries to deserialize JSON data. Deserialization converts the JSON data so that it can be serialized (written out) into a different format like Parquet or ORC.

• Hive JSON SerDe

• OpenX JSON SerDe

• Amazon Ion Hive SerDe

Note

The Hive and OpenX libraries expect JSON data to be on a single line (not formatted), with records separated by a new line character.

Because Amazon Ion is a superset of JSON, you can use the Amazon Ion Hive SerDe to query non-Amazon Ion JSON datasets. Unlike the Hive and OpenX JSON SerDe libraries, the Amazon Ion SerDe does not expect each row of data to be on a single line. This feature is useful if you want to query JSON datasets that are in "pretty print" format or otherwise break up the fields in a row with newline characters.

Library names

Use one of the following:

org.apache.hive.hcatalog.data.JsonSerDe

org.openx.data.jsonserde.JsonSerDe

com.amazon.ionhiveserde.IonHiveSerDe

Additional resources

For more information about working with JSON and nested JSON in Athena, see the following resources:

• Create tables in Amazon Athena from nested JSON and mappings using JSONSerDe (AWS Big Data Blog)

• I get errors when I try to read JSON data in Amazon Athena (AWS Knowledge Center article)

• hive-json-schema (GitHub) – Tool written in Java that generates CREATE TABLE statements from example JSON documents. The CREATE TABLE statements that are generated use the OpenX JSON Serde.