aa833a711c
Problem Currently, the delta input source only supports reading from the latest snapshot of the given Delta Lake table. This is a known documented limitation. Description Add support for reading Delta snapshot. By default, the Druid-Delta connector reads the latest snapshot of the Delta table in order to preserve compatibility. Users can specify a snapshotVersion to ingest change data events from Delta tables into Druid. In the future, we can also add support for time-based snapshot reads. The Delta API to read time-based snapshots is not clear currently.
2.4 KiB
| id | title |
|---|---|
| delta-lake | Delta Lake extension |
Delta Lake is an open source storage framework that enables building a
Lakehouse architecture with various compute engines. DeltaLakeInputSource lets
you ingest data stored in a Delta Lake table into Apache Druid. To use the Delta Lake extension, add the druid-deltalake-extensions to the list of loaded extensions.
See Loading extensions for more information.
The Delta input source reads the configured Delta Lake table and extracts the underlying Delta files in the table's latest snapshot based on an optional Delta filter. These Delta Lake files are versioned Parquet files.
Version support
The Delta Lake extension uses the Delta Kernel introduced in Delta Lake 3.0.0, which is compatible with Apache Spark 3.5.x. Older versions are unsupported, so consider upgrading to Delta Lake 3.0.x or higher to use this extension.
Downloading Delta Lake extension
To download druid-deltalake-extensions, run the following command after replacing <VERSION> with the desired
Druid version:
java \
-cp "lib/*" \
-Ddruid.extensions.directory="extensions" \
-Ddruid.extensions.hadoopDependenciesDir="hadoop-dependencies" \
org.apache.druid.cli.Main tools pull-deps \
--no-default-hadoop \
-c "org.apache.druid.extensions.contrib:druid-deltalake-extensions:<VERSION>"
See Loading community extensions for more information.