Add Support for t.LOCK.UPDATE in Sequelize Transactions

[pushoo-sharma]

The current implementation of Sequelize transactions allows for the use of various lock modes to manage concurrent access. However, the explicit t.LOCK.UPDATE option is not yet documented or supported. This feature is crucial for scenarios where exclusive locks are required to prevent concurrent updates to a specific database row.

Downsides and Considerations

1. Increased Contention:

   • The use of exclusive locks with t.LOCK.UPDATE can potentially lead to increased contention, especially in high-traffic scenarios, as transactions will be waiting for exclusive access.

2. Performance Impact:

   • Exclusive locks have a performance impact, and careful consideration should be given to the trade-off between data consistency and system performance.

3. Deadlocks:

   • Explicit use of exclusive locks may increase the likelihood of deadlocks, and proper strategies should be in place to handle and resolve deadlocks when they occur.

Additional Considerations

1. Guidelines for Usage:

   • Provide guidelines in the documentation on when to use t.LOCK.UPDATE and considerations for scenarios with potential contention.

2. Community Feedback:

   • Encourage community feedback on the use of t.LOCK.UPDATE in different scenarios to gather insights into its effectiveness and potential issues.

Expected Outcome

The explicit documentation and support for the t.LOCK.UPDATE option in Sequelize transactions will empower developers to make informed decisions about when to use exclusive locks. It's essential to highlight potential downsides and considerations to guide in using this feature judiciously.

Related Links

• Sequelize Transactions Documentation