Migration Guide: Structured Streaming

• Upgrading from Structured Streaming 2.4 to 3.0

Note that this migration guide describes the items specific to Structured Streaming. Many items of SQL migration can be applied when migrating Structured Streaming to higher versions. Please refer Migration Guide: SQL, Datasets and DataFrame.

Upgrading from Structured Streaming 2.4 to 3.0

• In Spark 3.0, Structured Streaming forces the source schema into nullable when file-based datasources such as text, json, csv, parquet and orc are used via spark.readStream(...). Previously, it respected the nullability in source schema; however, it caused issues tricky to debug with NPE. To restore the previous behavior, set spark.sql.streaming.fileSource.schema.forceNullable to false.