Undelete operation in trigger will fired, if you are restoring deleted record from the recycle bin. Example. If you deleted an account record, then it will be moved to recycle bin,if you restore the deleted account record from recycle bin, then undelete event in account object will get triggered.
Undelete operation in trigger will fired, if you are restoring deleted record from the recycle bin. Example. If you deleted an account record, then it will be moved to recycle bin,if you restore the deleted account record from recycle bin, then undelete event in account object will get triggered.
Trigger.New will holds the new value of the record, you can't use trigger.old in after undelete trigger event. To get more details, please check this link https://www.salesforce.com/us/developer/docs/apexcode/index_Left.htm#CSHID=apex_triggers_recovered_records.htm|StartTopic=Content%2Fapex_triggers_recovered_records.htm|SkinName=webhelp
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When you restore the record from Recycle Bin.
Check the below link.
https://developer.salesforce.com/forums/ForumsMain?id=906F00000008wWXIAY
Trigger.New will holds the new value of the record, you can't use trigger.old in after undelete trigger event. To get more details, please check this link https://www.salesforce.com/us/developer/docs/apexcode/index_Left.htm#CSHID=apex_triggers_recovered_records.htm|StartTopic=Content%2Fapex_triggers_recovered_records.htm|SkinName=webhelp