When would you use transaction isolation?
Transactions must be run at an isolation level of at least repeatable read to prevent lost updates that can occur when two transactions each retrieve the same row, and then later update the row based on the originally retrieved values.
What levels of transaction isolation are available?
InnoDB offers all four transaction isolation levels described by the SQL:1992 standard: READ UNCOMMITTED , READ COMMITTED , REPEATABLE READ , and SERIALIZABLE .
How does database isolation work?
Isolation is the database-level property that controls how and when changes are made, and if they become visible to each other, users, and systems. One of the goals of isolation is to allow multiple transactions to occur at the same time without adversely affecting the execution of each.
What does isolation mean in database?
In database systems, isolation determines how transaction integrity is visible to other users and systems. Isolation is typically defined at database level as a property that defines how or when the changes made by one operation become visible to others.
How does transaction security work in Salesforce.com?
Transaction Security is a feature that monitors Salesforce events in real time to spot potential trouble based on rules you create. With Transaction Security, you can create policies that consist of events, notifications, and actions. An event is anything that happens in Salesforce, including user clicks, record state changes, and measuring values.
What makes an event an event in Salesforce?
An event is anything that happens in Salesforce, including user clicks, record state changes, and measuring values. Events are immutable and timestamped. When you create a Transaction Security policy, you first pick a transaction, or event, to watch for and then you choose actions that are triggered when the event occurs.
When do you create a transaction security policy?
When you create a Transaction Security policy, you first pick a transaction, or event, to watch for and then you choose actions that are triggered when the event occurs. These rules and actions you create are called policies. Transaction security policies are created for many use cases, and you can extend them with Apex for customized protection.