Apex Triggers - 6 (Prevent Duplication of Records)

[@stutinayak-ti5xp]

There is a loop hole here . This trigger is also firing whenever we are updating the other fields in the same trigger. I guess there has to be a oldmap check for the name here in order to avoid such scenario as during the course there are multiple triggers build on same object.

[@sfdcninjas]

Hi Stuti , we cannot say that it is loophole actually this trigger is checking duplicates whenever any fields updates but the thing is it is only checking for names.

[@mayanksharma139]

@@sfdcninjas As Stuti said, We have to compare the old n value in order to prevent duplication otherwise it throw an error even if user update the record without chaning it's name as the record having the same name present in database

[@krishnaCasukhela]

@@sfdcninjas, normally account names are not updated from the front end. so I don't understand why you are using trigger.isUdpate, it should be only trigger.isInsert..

[@footballtalkswithsoham4430]

Thanks for the help

[@DS12399]

instead of creating a loop for list to map we can use Map existingAccMap = new Map(accList);

[@sfdcninjas]

nice suggestion Divya thanks

[@agamyashvant5545]

at line 17, we need to add null check isn't?

[@prasadpj8577]

This will fail for update operation when we click edit and save without even changing name

[@naveenyalamala]

public static void preventDuplicateRecord(List accList){ // Collect unique account names (normalized to lowercase) Set newAccNames = new Set(); for (Account acc : accList) { if (acc.Name != null) { newAccNames.add(acc.Name.toLowerCase()); } } // Query existing accounts with names in the set List existingAccounts = [ SELECT Id, Name FROM Account WHERE Name IN :newAccNames ]; // Collect existing account names and their IDs Set existingAccNames = new Set(); Map existingNameToIdMap = new Map(); for (Account acc : existingAccounts) { existingAccNames.add(acc.Name.toLowerCase()); existingNameToIdMap.put(acc.Name.toLowerCase(), acc.Id); } // Flag duplicate records for (Account acc : accList) { if (acc.Name != null) { String normalizedName = acc.Name.toLowerCase(); // Check if the name exists and if it's not the same as the current record if (existingAccNames.contains(acc.Name.toLowerCase()) && !existingNameToIdMap.get(acc.Name.toLowerCase()).equals(acc.Id)) { acc.addError('Duplicate Account Name detected: ' + acc.Name); } } } }

[@dharmeshgupta3957]

very informative and helpful!!

[@sfdcninjas]

Thank you Dharmesh

[@ambritkumarsahu5179]

Bro.. instead of using a map , can't we use a List there to store the Names.. Because we are not using the Values of the Map, only using the Keys.. Isn't it? Or am I missing something?

[@sfdcninjas]

Hi Buddy , sorry for late reply , List can have duplicate values that's why we are using map here.

[@sagarbora7768]

@@sfdcninjas But we could use set it's gonna have distinct values, Correct me if I'm wrong.

[@naveenyalamala]

You are trying to insert 4 Account records, all with the same name, and that name does not currently exist in the database. Will it allow Insertion ?

[@JShorts511]

The following code will not allow /*Trigger Scenario: Write a trigger to prevent duplicate accounts based on name whenever an Account is inserted or updated. Scenario is to validate records before they are saved to database. so we use before trigger. context variables to access runtime contexts are Trigger.isInsert and Trigger.isUpdate*/ trigger AccountTrigger on Account(before insert,before update){ //set to collect Account Name from triggering records. List accNames=new List(); //accessing run time context if(Trigger.isBefore){ if(Trigger.isInsert){ //iterating over triggering records for(Account acc:Trigger.new){ accNames.add(acc.Name); } } if(Trigger.isUpdate){ //iterating over triggering records for(Account acc:Trigger.new){ //checking whether the account's Name is changed or not if(acc.Name != Trigger.oldMap.get(acc.Id).Name){ accNames.add(acc.Name); } } } } List accList=[SELECT Id,Name FROM Account WHERE Name IN:accNames]; set accNameSetToCheckDups=new set(); //Map to get number of accounts with same name Map accNamesCountwithName=new Map(); //iterating over accNames if(!accNames.isEmpty()){ for(String acctName:accNames){ if(!accNamesCountwithName.containsKey(acctName)){ accNamesCountwithName.put(acctName,0); }else { Integer count=accNamesCountwithName.get(acctName)+1; accNamesCountwithName.put(acctName,count); } } } //iterating over accList to collect existing names if(!accList.isEmpty()){ for(Account acc:accList){ accNameSetToCheckDups.add(acc.Name); } } //iterating over Triggering records to prevent duplicates if(!accNameSetToCheckDups.isEmpty() || accNamesCountwithName.keySet() !=null ){ //if triggering records has the same name more than one (If we are inserting /updating with same name at a time) for(Account acc:Trigger.new){ if(accNamesCountwithName.get(acc.Name)>1 || accNameSetToCheckDups.contains(acc.Name)){ acc.addError('Account already exists with the same name'); } } } }

[@naveenyalamala]

@@JShorts511 thank you

[@jatinneelay5926]

there should be if else and in else we should add non duplicate record in map so that within trigger scope we dont insert duplicates

[@rahulkumbhare5454]

Hi SFDC Ninja, can't we simply check the size of accList and determine duplicate account name present or not? The accList will have values only if the Accounts with the given names are already present. So, if the size is more than 0, it means we already have accounts in the database with name which are being inserted. Please correct if this understanding is wrong. Thanks

[@sfdcninjas]

Hi Rahul , see Checking the size of accNames instead of accList may not be suitable for bulk records. also Without querying the accList, you won't have access to the actual existing accounts with duplicate names. This means you cannot perform any specific actions or validations on those existing accounts. It may limit your ability to handle duplicates effectively or implement customized logic based on the existing account records.

[@soumya1713]

if you have more than 50k records then how can you handle it

[@opeyemi_salesforce_journey]

you might need to go for more async solution like queueable or batch apex

[@prasadpj8577]

Please upload a scenario to avoid trigger using Map

[@sfdcninjas]

Hi Prasad sure i will try to create a video on it .

[@rohantelang1817]

In this solution, there is many "for loops".can any one provide solution by reducing "for loops"?

[@lokeshv8999]

trigger CandidateTrigger on Account(Before insert,Before Update){ if(trigger.isbefore && (trigger.isinsert ||trigger.isUpdate ){ listaccrecord=[select id,name from account]; for(Account accnew:Trigger.new){ for(Account accold:accrecord){ if(accnew.name==accold.name){ accnew.name.adderror('Duplicate Name cannot be entered again'); } } } } }

[@SathishKumar-ok6tu]

@@lokeshv8999 List accrecord = [select id,name from account]; As per Salesforce Governor Limits, SOQL will return maximum 50K records. This will fail if our org contains more than 50K account records. Also, this code contains nested for loop which will affect performance.

[@praveenbuddi190]

goto VScode settings--- settings- search for Font -- default is 14- to increase- 20-24 font size...

[@sfdcninjas]

Thank you again

[@praveenbuddi190]

bro, small suggetion increse font size.

[@sfdcninjas]

sure bro and thank you for suggestion

[@ramadevikantamani3057]

Scenario will fail when we update other fields in the account other than name .

[@sfdcninjas]

Hi , In this scenario I have explained trigger to prevent duplication of account record based only on Name field you can add other fields to prevent duplication. Thank you

[@deboleenadutta1448]

what is the peoblem with the simple solution given below.. if anybody has idea let me know trigger PreventDupl on Account(before Insert , before delete){ if(trigger.isBefore && trigger.isDelete){ for(account acc : trigger.new){ integer countedRec = [select count(id) from Account where name = acc.name]; if(countedRec > 0){ acc.addError('Already an account is existing with the provided name'); } } } }

[@rupesh-patil011]

@deboleenadutta1448 You are doing SOQL inside for loop. It will hit the governor limit and before delete is not required.

[@deboleenadutta1448]

@@rupesh-patil011 thanks … yes before delete is my mistake…

[@sfdcakshul]

Informative 👍

[@sfdcninjas]

Thank you

[@praveennanda7521]

trigger AccountTrigger on Account(before insert, before update) { if(trigger.isbefore && (trigger.isinsert || trigger.isupdate)) { for(Account acc :trigger.new) { Integer accountCount = [Select count() from Account where Name =: acc.Name]; if(accountCount>0) acc.Name.addError('Please enter the last name as uniquly'); } } }

[@ShikhaKanaujia-k7d]

avoid using SOQL inside for loop

[@BusraYildiz-t3u]

trigger ApexTrigger6 on Account (before insert,before Update) { Set Names = new Set(); If(Trigger.isBefore){ For(Account acc: Trigger.new){ if(trigger.isInsert|| acc.Name!=trigger.oldMap.get(acc.id).Name){ Names.add(acc.Name); } } } List ExistingName = New List(); For(Account acc:[Select Name, Id From Account Where Name In:Names]){ ExistingName.add(acc.Name); } For(Account acc: trigger.new){ if(ExistingName.Contains(acc.name)) acc.Name.addError('duplicate'); } } here is another approach