What is the role of a transaction manager in global transactions?

In the context of global transactions, the transaction manager plays a critical role in ensuring that all operations across various resource managers are conducted in a coordinated manner. This involves overseeing multiple transactions within different systems or databases, particularly in scenarios where a single transaction may span several resources.

The transaction manager is responsible for managing the commit or rollback of all these operations, ensuring that either all changes are applied successfully or none at all. This is crucial in maintaining data consistency and integrity throughout various systems that participate in the transaction.

By coordinating the different resource managers, the transaction manager enables a structured and reliable approach to handle complex transactions, preventing issues that could arise from partial transaction completions. This makes the effective management of global transactions a vital aspect of applications that rely on multiple data sources or services.