v2.0.0-spark-3.1.2

[dmetasoul01]

1. Catalog refactoring

1. Replacing the Cassandra protocol with the Postgres protocol
2. metadata Use PG protocol to rewrite table operations, partition operations, and data operation related functions, and use transaction mechanism to achieve data submission collision detection to ensure ACID attributes
3. Interface with Spark and metadata, translate Spark-related metadata operations into the underlying interface, and realize the cross-border distribution between the upper computing platform and the underlying development storage layer

2. DDL

1. Spark SQL related DDL statements (create alter, etc.) transformation
2. Spark DataFrame | DataSet related DDL statement (save, etc.) transformation

3. Data Writing

1. Transformation of SparkSQL-related DML statements (insert into, update, etc.)
2. Spark DataFrame | DataSet related DML statements (write function, etc.)
3. LakeSoulTable upsert function transformation
4. LakeSoulTable compaction function transformation, and support to mount to hive

4. Data Reading

1. A variety of ParquetScan transformation, remove the write version sorting mechanism, adapt to the new metadata UUID file list format
2. LakeSoulTable adds a snapshot reading function to read the historical content according to the specified partition version
3. LakeSoulTable adds a history rollback function to roll back to a certain historical version of the specified partition
4. Added and modified the default MergeOprator function to make it easier for users to operate Merge results

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This discussion was created from the release v2.0.0-spark-3.1.2.