add support rollback running txn to 1.2

[zhangxu19830126]

User description

What type of PR is this?

• API-change
• BUG
• Improvement
• Documentation
• Feature
• Test and CI
• Code Refactoring

Which issue(s) this PR fixes:

issue #4083

What this PR does / why we need it:

add support rollback running txn

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PR Type

Enhancement, Tests

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Description

• Simplified the close method in column_cache.go by removing the locking mechanism and returning nil.
• Introduced a runningSQL atomic boolean in operator.go to track the execution state of SQL transactions.
• Enhanced Commit and Rollback methods to prevent operations if SQL is currently running.
• Updated EnterRunSql and ExitRunSql methods to modify the runningSQL state.
• Added comprehensive tests in operator_test.go to verify the new behavior of transaction operators, including checks for running SQL, lock skipping, and lock table presence.

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Changes walkthrough 📝

	Relevant files
Enhancement	column_cache.go Simplify column cache close method                                              pkg/incrservice/column_cache.go Removed locking mechanism in the close method. Simplified the close method to return nil. +1/-3      operator.go Add state tracking for running SQL transactions                    pkg/txn/client/operator.go Added runningSQL atomic boolean to track SQL execution state. Added checks in Commit and Rollback to prevent operations during running SQL. Updated EnterRunSql and ExitRunSql to modify runningSQL state. +11/-0
Tests	operator_test.go Add tests for transaction operator enhancements                    pkg/txn/client/operator_test.go Added tests to ensure Commit and Rollback cannot be performed during running SQL. Added tests for lock skipping and lock table presence. +103/-0

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PR Reviewer Guide 🔍

⏱️ Estimated effort to review: 3 🔵🔵🔵⚪⚪

🧪 PR contains tests

🔒 No security concerns identified

⚡ Key issues to review Error Handling The use of util.GetLogger().Fatal() in Commit and Rollback methods may abruptly terminate the program. Consider using a more graceful error handling approach. Duplicate Code The error message "commit on running txn" is used for both Commit and Rollback methods. Consider using a more specific error message for Rollback.

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PR Code Suggestions ✨

Category	Suggestion	Score
Possible bug	Correct error message for illegal rollback operation The error message for rollback is incorrect. It mentions "commit" instead of "rollback". Update the error message to accurately reflect the operation being performed. pkg/txn/client/operator.go [560-562] if tc.runningSQL.Load() { - util.GetLogger().Fatal("commit on running txn") + util.GetLogger().Fatal("Cannot rollback while SQL is running. Ensure all SQL operations are completed before rolling back.") } Apply this suggestion Suggestion importance[1-10]: 9 Why: This suggestion corrects a misleading error message, which is crucial for accurate debugging and understanding of the code's behavior, addressing a potential bug.	9
Error handling	Return an error instead of terminating the program for better error handling Instead of using Fatal, which will terminate the program, consider returning an error. This allows the caller to handle the error gracefully and potentially recover from the situation. pkg/txn/client/operator.go [521-523] if tc.runningSQL.Load() { - util.GetLogger().Fatal("commit on running txn") + return fmt.Errorf("cannot commit while SQL is running: ensure all SQL operations are completed before committing") } Apply this suggestion Suggestion importance[1-10]: 8 Why: This suggestion enhances error handling by allowing the program to handle errors gracefully instead of terminating, which is a significant improvement in robustness and flexibility.	8
Enhancement	Improve error message clarity for illegal commit operation Consider using a more descriptive error message in the Fatal call. Instead of a generic message, provide more context about why committing during a running SQL operation is not allowed. pkg/txn/client/operator.go [521-523] if tc.runningSQL.Load() { - util.GetLogger().Fatal("commit on running txn") + util.GetLogger().Fatal("Cannot commit while SQL is running. Ensure all SQL operations are completed before committing.") } Apply this suggestion Suggestion importance[1-10]: 7 Why: The suggestion improves the clarity of the error message, providing more context for the developer, which enhances maintainability and debugging.	7
Best practice	Improve method naming for better code readability Consider using a more specific method name than Load() for the runningSQL atomic boolean. A method name like IsRunning() would be more descriptive and improve code readability. pkg/txn/client/operator.go [521] -if tc.runningSQL.Load() { +if tc.runningSQL.IsRunning() { Apply this suggestion Suggestion importance[1-10]: 5 Why: While the suggestion improves readability, it requires a change in the atomic library or wrapper, which may not be feasible or necessary if the method is standard.	5