ClassNotFoundUsingFlinkSQLWriteDeltaTable: Technical Support Guide
This article provides a detailed guide on the topic of writing data using Flink SQL and Delta Table, with a particular focus on the error caused by a java.lang.NoSuchMethodError: scala.jdk. exception. The article covers key concepts related to Flink SQL, Delta Tables, and the mentioned error, and includes subtitles, paragraphs, and code blocks as necessary.
Background: Flink SQL and Delta Tables
Flink SQL is a SQL engine built on top of Apache Flink, a powerful stream processing framework. Flink SQL allows users to write SQL queries to process data streams in real time, and supports various data sources such as Kafka, HDFS, and Delta Tables.
Delta Tables, on the other hand, is a high-performance, open-source storage layer that is built on top of Parquet. It provides ACID transactions, scalable metadata handling, and unifies streaming and batch data processing. Delta Tables can be used as a data source or sink in Flink SQL queries.
The Error: ClassNotFoundUsingFlinkSQLWriteDeltaTable
When writing data to Delta Tables using Flink SQL, some users have encountered the following exception:
This error typically occurs when there is a version mismatch between the Scala libraries used by Flink and the Scala libraries used by Delta Tables.
Solution: Ensuring Compatible Versions
To resolve the ClassNotFoundUsingFlinkSQLWriteDeltaTable error, it is necessary to ensure that the versions of Scala libraries used by Flink and Delta Tables are compatible.
At the time of writing, the compatible versions of Scala libraries for Flink SQL and Delta Tables are:
- Flink: Scala 2.11 or 2.12
- Delta Tables: Scala 2.12
Therefore, it is recommended to use Flink with Scala 2.12 when working with Delta Tables.
Code Example: Writing Data to Delta Tables using Flink SQL
The following is an example of how to write data to a Delta Table using Flink SQL:
In this example, the Flink SQL table delta\_table is backed by a Delta Table located at delta-table-path. Data is inserted into the table using the INSERT INTO statement.
Summary and References
In this article, we have covered the topic of ClassNotFoundUsingFlinkSQLWriteDeltaTable, including the background on Flink SQL and Delta Tables, the error caused by a java.lang.NoSuchMethodError: scala.jdk. exception, and the solution to ensure compatible versions. The key concepts covered include:
- Flink SQL
- Delta Tables
- Version compatibility
The following references provide more information on the topics covered in this article: