[Task]: Polish Beam SQL user experience

[ahmedabu98]

What needs to happen?

Some features are missing:

• Support DDL for DATABASEs (create, use, drop) #35641
• If a user has set a DATABASE, they should be able to read an existing table without having to run a redundant CREATE EXTERNAL TABLE... #35787
• We should infer the table name from the reference, instead of requiring an explicit LOCATION property #35787
• Support SHOW statements #36509
• Support ALTER TABLE, CATALOG #36571
• Add Iceberg CDC table

For reference, Flink and Spark syntax

Issue Priority

Priority: 2 (default / most normal work should be filed as P2)

Issue Components

• [ ] Component: Python SDK
• [x] Component: Java SDK
• [ ] Component: Go SDK
• [ ] Component: Typescript SDK
• [x] Component: IO connector
• [ ] Component: Beam YAML
• [ ] Component: Beam examples
• [ ] Component: Beam playground
• [ ] Component: Beam katas
• [ ] Component: Website
• [ ] Component: Infrastructure
• [ ] Component: Spark Runner
• [ ] Component: Flink Runner
• [ ] Component: Samza Runner
• [ ] Component: Twister2 Runner
• [ ] Component: Hazelcast Jet Runner
• [ ] Component: Google Cloud Dataflow Runner