Fix to not drop the metadata table when renaming table

[KodaiD]

Description

This PR updates the rename table feature to avoid dropping the metadata table if it is empty.

Currently, the feature drops the metadata table if it is empty. Therefore, it can fail due to the metadata table NOT FOUND exception when inserting new metadata if only one table exists:

1. Delete the old metadata.
2. Drop the empty metadata table.
3. Rename the table in the storage.
4. Insert a new metadata. <- TABLE NOT FOUND!

Related issues and/or PRs

• Add rename table #3021

Changes made

• Updated to avoid dropping the metadata table even if it is empty in renameTable.
• Updated unit tests.
• Added integration tests.

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

N/A

[KodaiD]

/gemini review

[gemini-code-assist]

Code Review

This pull request correctly addresses a potential NOT FOUND exception when renaming a table if the metadata table does not exist. The fix, which involves ensuring the metadata table is recreated, is sound. The addition of unit and integration tests is also great, especially the integration test that specifically covers the scenario where only one table exists. I have a couple of suggestions to improve the maintainability of the test code by reducing duplication.

[Copilot]

Pull Request Overview

This PR fixes a bug in the rename table feature where the metadata table was not being recreated if it didn't exist, causing potential failures when inserting new metadata after renaming.

Key Changes:

• Modified JdbcAdmin.renameTable() to recreate the metadata table if it doesn't exist by changing the addTableMetadata parameter from false to true
• Added integration tests to verify table renaming works correctly when only one table exists in a namespace
• Updated unit tests to verify metadata table recreation SQL statements are executed during rename operations

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
core/src/main/java/com/scalar/db/storage/jdbc/JdbcAdmin.java	Changed parameter in addTableMetadata call to enable metadata table recreation
core/src/test/java/com/scalar/db/storage/jdbc/JdbcAdminTest.java	Added expected SQL statements for metadata table creation across all database types
integration-test/src/main/java/com/scalar/db/api/DistributedTransactionAdminIntegrationTestBase.java	Added integration test for renaming when only one table exists
integration-test/src/main/java/com/scalar/db/api/DistributedStorageAdminIntegrationTestBase.java	Added integration test for renaming when only one table exists

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[Torch3333]

LGTM, thank you!

[komamitsu]

LGTM! 👍

[brfrn169]

LGTM! Thank you!

[KodaiD]

@komamitsu @Torch3333 I revised this PR to avoid dropping the metadata table instead of recreating it. Please take a look when you get a chance.

[Torch3333]

LGTM, thank you!

[feeblefakie]

LGTM! Thank you!