Add drop column

[KodaiD]

Description

This PR adds support for dropping columns in ScalarDB.

Currently, ScalarDB does not support dropping columns and users must recreate tables to remove unwanted columns. This feature will provide more flexibility in managing database schemas without requiring recreating tables.

Related issues and/or PRs

• Support ifNotExists in add column #2960

Changes made

• Added dropColumnFromTable method in the Admin interface.
• Added unit tests for the method.
• Added integration tests for the method.

Checklist

• I have commented my code, particularly in hard-to-understand areas.
• I have updated the documentation to reflect the changes.
• I have considered whether similar issues could occur in other products, components, or modules if this PR is for bug fixes.
• Any remaining open issues linked to this PR are documented and up-to-date (Jira, GitHub, etc.).
• Tests (unit, integration, etc.) have been added for the changes.
• My changes generate no new warnings.
• Any dependent changes in other PRs have been merged and published.

Additional notes (optional)

N/A

Release notes

Added support for dropping columns in ScalarDB.

[Copilot]

Pull Request Overview

This PR adds support for dropping columns in ScalarDB by implementing the dropColumnFromTable method in the Admin interface. This enhancement allows users to remove unwanted columns without recreating entire tables.

• Adds dropColumnFromTable method to the Admin interface with validation to prevent dropping partition keys, clustering keys, or indexed columns
• Implements the method across all storage adapters (JDBC, Cassandra, DynamoDB, Cosmos DB) with appropriate support or exception handling
• Includes comprehensive test coverage for various scenarios including error cases and edge conditions

Reviewed Changes

Copilot reviewed 33 out of 33 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
core/src/main/java/com/scalar/db/api/Admin.java	Adds dropColumnFromTable method definitions with validation logic
core/src/main/java/com/scalar/db/storage/jdbc/JdbcAdmin.java	Implements column dropping using ALTER TABLE DROP COLUMN SQL statements
core/src/main/java/com/scalar/db/storage/cassandra/CassandraAdmin.java	Implements column dropping using Cassandra's SchemaBuilder
core/src/main/java/com/scalar/db/storage/dynamo/DynamoAdmin.java	Throws UnsupportedOperationException as DynamoDB doesn't support column dropping
core/src/main/java/com/scalar/db/storage/cosmos/CosmosAdmin.java	Throws UnsupportedOperationException as Cosmos DB doesn't support column dropping
Various test files	Comprehensive test coverage including integration tests and unit tests for all implementations

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[komamitsu]

LGTM, thank you!

[brfrn169]

Overall LGTM. Left minor comments. PTAL!

[Torch3333]

LGTM, thank you!

[feeblefakie]

The code looks good. Left minor comments/suggestions on the error messages.

[brfrn169]

Left several comments. PTAL!

[brfrn169]

LGTM! Thank you!

[feeblefakie]

LGTM! Thank you!