Trigger Context Variables

All triggers define implicit variables that allow developers to access run-time context. These variables are contained in the System.Trigger class.

Here are the trigger context variables.

Variable	Usage
`isExecuting`	Returns `true` if the current context for the Apex code is a trigger, not a Visualforce page, a web service, or an `executeanonymous()` API call.
`isInsert`	Returns `true` if this trigger was fired due to an insert operation, from the Salesforce user interface, Apex, or the API.
`isUpdate`	Returns `true` if this trigger was fired due to an update operation, from the Salesforce user interface, Apex, or the API.
`isDelete`	Returns `true` if this trigger was fired due to a delete operation, from the Salesforce user interface, Apex, or the API.
`isBefore`	Returns `true` if this trigger was fired before any record was saved.
`isAfter`	Returns `true` if this trigger was fired after all records were saved.
`isUndelete`	Returns `true` if this trigger was fired after a record is recovered from the Recycle Bin. This recovery can occur after an undelete operation from the Salesforce user interface, Apex, or the API.
`new`	Returns a list of the new versions of the sObject records. This sObject list is only available in `insert`, `update`, and `undelete` triggers, and the records can only be modified in `before` triggers.
`newMap`	A map of IDs to the new versions of the sObject records. This map is only available in `before update`, `after insert`, `after update`, and `after undelete` triggers.
`old`	Returns a list of the old versions of the sObject records. This sObject list is only available in `update` and `delete` triggers.
`oldMap`	A map of IDs to the old versions of the sObject records. This map is only available in `update` and `delete` triggers.
`operationType`	Returns an enum of type `System.TriggerOperation` corresponding to the current operation. Possible values of the System.TriggerOperation enum are: `BEFORE_INSERT`, `BEFORE_UPDATE`, `BEFORE_DELETE`,`AFTER_INSERT`, `AFTER_UPDATE`, `AFTER_DELETE`, and `AFTER_UNDELETE`. If you vary your programming logic based on different trigger types, consider using the `switch` statement with different permutations of unique trigger execution enum states.
`size`	The number of records processed in a trigger invocation. DML operations that include over 200 records are processed in batches, and the trigger is invoked for each batch. `Trigger.size` includes only the number of records in the current batch, not the total number of records in the DML operation.

The record firing a trigger can include an invalid field value, such as a formula that divides by zero. In this case, the field value is set to null in these variables:

new
newMap
old
oldMap

For example, in this simple trigger, Trigger.new is a list of sObjects and can be iterated over in a for loop. It can also be used as a bind variable in the IN clause of a SOQL query.

This trigger uses Boolean context variables such as Trigger.isBefore and Trigger.isDelete to define code that only executes for specific trigger conditions:

See Also