Active Record Transaction

1. ActiveRecord Transaction Shiva Bhusal

2. - Transactions are protective blocks
- Makes sense if some operations are interdependent.
- Transactions enforce the integrity of the database
- Guard the data against program errors or database break-downs
Introduction

3. - Basically you should use transaction blocks whenever you have a number
of statements that must be executed together or not at all.
- The classic example is a transfer between two accounts where you can
only have a deposit if the withdrawal succeeded and vice versa
Use Cases

4. - save and destroy are automatically wrapped in a transaction
Alternative way

5. - Exceptions thrown within a transaction block will be propagated (after
triggering the ROLLBACK)
- ActiveRecord::Rollback exception, triggers a ROLLBACK when raised
- not be re-raised by the transaction block.
Transaction Rollback Triggers

6. - There are two types of callbacks associated with committing and rolling
back transactions:
- after_commit
- after_rollback
Callbacks

7. Thanks

8. References
http://api.rubyonrails.org/classes/ActiveRecord/Tran
sactions/ClassMethods.html
http://markdaggett.com/blog/2011/12/01/transaction
s-in-rails/
https://cbabhusal.wordpress.com/2015/12/15/activere
cord-callbacks-and-the-order-in-which-they-get-
executed/