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imaliveagain Trigger not updating a lookup field on a parent record
Hi my skills are pretty basic however I think my task is pretty basic with this trigger. I've looked on the boards and found people answering this question but I am missing something and was hoping someone could let me know what I'm missing. Because you can't update a lookup field on a parent record master-detail through a workflow rule I am writing a trigger to do it.
Scenario:
I have three objects IC_Asset__c is the parent of a master-detail relationship with Checkin_Checkout_History__c . On IC_Asset object there is a lookup field called In_possession_of__c to a Staff__c object. On Checkin_Checkout_History__c there is a lookup field called Asset_History__c to the same Staff__c object.
I want to write the contents of Asset_History__c field to In_possesion_of__c field on IC_Asset__c after an edit on Checkin_Checkout_History__c.
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trigger SetInPossessionOf on Checkin_Checkout_History__c (before update) {
//create a set of all unique IC_Asset ids
Set<Id> assetIds = new Set<Id>();
for (Checkin_Checkout_History__c chk : Trigger.new)
// Add ids of lookup on Checkin_Checkout_History__c to assetIds
assetIds.add(chk.Asset_Lookup__c);
// create a map so that IC_Assets are locatable by Id
Map<Id, IC_Asset__c> icaMap = new Map<Id, IC_Asset__c>(
[SELECT Id,In_possession_of__c,text_field_asset__c FROM IC_Asset__c WHERE Id IN :assetIds]);
for (Checkin_Checkout_History__c chk : Trigger.new){
// get the IC_Asset__c from the map by its id
icaMap.get(chk.Asset_Lookup__c).In_possession_of__c = chk.Staff__c;
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Nothing happens.
I can copy field to field on the record
chk.text_field__c = chk.text_field_chkout__c;
I can even copy from the parent lookup to a text field
chk.text_field_chkout__c= icaMap.get(chk.Asset_Lookup__c).In_possession_of__c;
But when I try to copy up to the parent I get nothing whether copying to a lookup or text field
icaMap.get(chk.Asset_Lookup__c).text_field_asset__c = chk.text_field_chkout__c;
Please help, thanks
you update the IC_Asset__c records only within the trigger context, but you never save these changed records back into the database.
The records are the values in the icaMap, so after the last for-loop, add an
That should do it
Arnt
All Answers
you update the IC_Asset__c records only within the trigger context, but you never save these changed records back into the database.
The records are the values in the icaMap, so after the last for-loop, add an
That should do it
Arnt
I think I see what you're trying to do.
You have a child record Checkin_Checkout_History__c. When this record is edited, you want it to update the Parent Record Object IC_Asset__c.
This is why it's not working.
Your Before Trigger is updating Checkin_Checkout_History__c objects and not the Parent Object. So when your trigger is fired, the Parent Object's field gets written -- but not actually updated. Basically, what you're doing is like going to edit the parent record - but not actually saving it.
I would do this:
trigger SetInPossessionOf on Checkin_Checkout_History__c (before update) { //create a set of all unique IC_Asset ids Set<Id> assetIds = new Set<Id>(); for (Checkin_Checkout_History__c chk : Trigger.new) // Add ids of lookup on Checkin_Checkout_History__c to assetIds assetIds.add(chk.Asset_Lookup__c); // create a map so that IC_Assets are locatable by Id Map<Id, IC_Asset__c> icaMap = new Map<Id, IC_Asset__c>([SELECT Id,In_possession_of__c,text_field_asset__c FROM IC_Asset__c WHERE Id IN :assetIds]); for (Checkin_Checkout_History__c chk : Trigger.new){ // get the IC_Asset__c from the map by its id icaMap.get(chk.Asset_Lookup__c).In_possession_of__c = chk.Staff__c;} //create list of ParentObjects List<IC_Asset__c> ParentObjectList = icaMap.Values(); //save the ParentObjects update ParentObjectList;basically you update the parent record, shove those parents into a list, then "save" the parents by doing an update.
My only concern here is if you have multiple checkin_checkout_history__c objects related to the same parent and have difference Staff__c values. Which one would you expect to get written to the parent?
Brian and I basically have the same idea. I think it is not necessary to copy the records from the Map to a list before updating, but the result will be the same.
I agree with Brian's concern, the last checkin_checkout_history__c record will overwrite any changes from other records to the same parent record. But maybe that is how you want it to work, it really depends on your business case.
Yes!! That worked thank you.
It's a checkout type system and I want to have it overwrite the lookup with no record on the staff object except when the asset is currently assigned to them. Conceptually it's like moving an item from one bin to another bin. The record of where it's been will be on the asset instead of the staff object.
Thanks for the quick response.
Ahab,
I like your solution of updating directly from the map.values()...
I've gotten in the habit of shoving everything in lists just for degbug purposes. Plus, I tend to declare all my variables at the top of my trigger/class based on my design. This way if I dev and I forget to use a variable I know I either screwed up in my dev or in my design:)
Not elegant, but it works:)