Aidan Harding aidan-harding

I have a scenario where an external system is calling Salesforce API, causing a trigger to run. That trigger needs to delete EmailMessage records where the RelatedTo field is an Account.

We're getting UNABLE_TO_LOCK_ROW errors when the external system's API calls overlap and the trigger attempts to delete multiple emails on the same Account at the same time.

This is totally understandable based on how [record-locking works][1]. RelatedTo is either a required lookup or a Master-Detail so deleting the EmailMessage would require a lock on the related Account.

I tried to solve the problem by adding FOR UPDATE to the query in the trigger where it fetches the EmailMessage records.

But, we still observe UNABLE_TO_LOCK_ROW as a DmlException (if it were a QueryException, then that might be due to the 10-second limit timing out).

	/**
	* @author [email protected]
	* @date 29/08/2024
	* @description A map where the items are lists of items and you can provide a function for how values map to keys.
	* Oh, if we had generics....
	*/

	public class MultiMap {
	private Map<Object, List<Object>> theMap;
	private Type listType;

	// Note that WITH USER_MODE is not allowed in Anonymous Apex!

	List<EntityDefinition> entityDefinitions = [
	SELECT QualifiedApiName
	FROM EntityDefinition
	WITH USER_MODE
	];

	// Now entityDefinitions is a list of objects accessible by the current user,
	// a bit like Schema.getGlobalDescribe().keySet() but faster!

	/**
	* @author [email protected]
	* @date 22/08/2023
	* @description For a given Long text field, when it changes append the old value to the new value with a new line (\n).
	* If the field changes to blank/null then the old value remains.
	*
	* Example:
	*
	* Old Value New Value Expected Value
	* --------------------------------------------

	public with sharing class InsertAccountsQueueable implements Queueable, Finalizer {

	private Integer nAccounts;
	private String name;

	public InsertAccountsQueueable(Integer nAccounts, String name) {
	this.nAccounts = nAccounts;
	this.name = name;
	}

	/**
	* @author [email protected]
	* @date 21/10/2020
	* @description For implementing the Client Credentials OAuth Flow using Named Credentials to store the client id
	* and client secret. The initiate method is a dummy one, going straight to the callback, which does a callout to the
	* token endpoint. Refreshing is also a dummy, simply obtaining a new token with the original client id and secret.
	*/

	public with sharing class ClientCredentialsAuthProvider extends Auth.AuthProviderPluginClass {

	public class CovariantReturnTypes {

	virtual class X {
	virtual Object foo() { return 0; }
	}

	// I want to do this, but the compiler says "Method return types clash: String vs Object", see
	// https://ideas.salesforce.com/s/idea/a0B8W00000GdXOCUA3/support-covariant-return-types-in-apex
	class Y extends X {
	override String foo() { return ''; }

	private class IsYearChanged extends nebc.TriggerContextBooleanFunction {

	public override Boolean isTrueFor(SObject oldRecord, SObject newRecord) {
	Term__c oldTerm = (Term__c)oldRecord;
	Term__c newTerm = (Term__c)newRecord;
	return Math.abs(oldTerm.Start_Date__c.year() - newTerm.Start_Date__c.year()) > 0;
	}
	}

	/**
	* @author [email protected]
	* @date 15/11/2021
	*/

	@IsTest
	private class TransformationTest {

	@IsTest
	static void passThroughSObjectToOtherSObject() {