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Description

This error occurs when the definition (schema) of a table involved in an ongoing transaction is altered by another process. MariaDB detects this concurrent modification and aborts the current transaction to maintain data integrity and prevent inconsistencies. It typically requires the transaction to be retried.

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Error Message

Table definition has changed, please retry transaction

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Known Causes

3 known causes

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Concurrent Schema Modification

Another database session or client executed a Data Definition Language (DDL) statement, such as ALTER TABLE or TRUNCATE TABLE, on a table actively used by your transaction.

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Application DDL Race Condition

The application's logic performs DDL operations on tables concurrently with active transactions, leading to a race condition where schema changes conflict with ongoing data access.

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Unsynchronized Schema Migrations

Automated database schema migration tools or scripts were executed on the database while transactions were actively accessing the tables undergoing structural changes.

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Solutions

4 solutions available

1. Retry the Transaction easy

The simplest solution is to re-execute the operation that caused the error.

1

Identify the SQL statement that failed and caused the 'Concurrent Table Definition Change' error. This could be an `ALTER TABLE`, `CREATE TABLE`, `DROP TABLE`, or similar DDL statement.

2

Re-execute the failed SQL statement. MariaDB's internal locking mechanisms might have resolved the conflict since the initial attempt.

ALTER TABLE your_table_name ADD COLUMN new_column INT;

2. Identify and Resolve Concurrent Operations medium

Find and stop other operations that are modifying the same table.

1

Check for active or long-running DDL operations on the same table. You can do this by examining the MariaDB process list.

SHOW FULL PROCESSLIST;

2

If you find other DDL statements (e.g., `ALTER TABLE`) running on the same table, wait for them to complete. If they are stuck or unintended, you may need to terminate them.

KILL <process_id>;

3

Once conflicting operations are resolved, retry the original transaction.

3. Use a Staging Environment for Complex Changes medium

Perform complex schema changes in a test environment first to avoid production conflicts.

1

Create a clone of your production database in a staging or development environment.

2

Apply your intended schema changes (e.g., `ALTER TABLE`) to the staging database.

ALTER TABLE your_table_name MODIFY COLUMN existing_column VARCHAR(255);

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Thoroughly test your application against the staging database to ensure the changes are compatible and perform as expected.

4

Schedule a maintenance window for your production environment and apply the validated schema changes during that time.

4. Review and Optimize Application Logic advanced

Ensure your application doesn't trigger unintended concurrent schema modifications.

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Analyze your application code, especially any parts that dynamically generate or execute DDL statements.

2

Implement proper locking mechanisms or ensure DDL operations are serialized and executed only when no other DDL is in progress on the target table.

3

Consider using stored procedures or a dedicated migration tool to manage schema changes, which can provide better control over concurrency.

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Related Errors

5 related errors

MariaDB Error 1412: Concurrent Table Definition Change