Suppose "readOnlyField__c" is the field you want make readonly, then, Write a before update trigger. Check if the value of "readOnlyField__c" has changed like if (trigger.new.readOnlyField__c != trigger.old).readOnlyField__c)
Full Answer
What is a trigger in Salesforce?
Apex triggers enable you to perform custom actions before or after changes to Salesforce records, such as insertions, updates, or deletions. A trigger is Apex code that executes before or after the following types of operations: insert. update. delete.
How to make the field required using triggers?
How to make the field required using triggers? 1 You can set a field as REQUIRED via the Page Layout 2 You can set a field as REQUIRED using a Validation Rules (field will become mandatory based on specific criteria) 3 You can also use the Field Level Security at the profile level to define access to a field. 4 Via Triggers.
How do I invoke apex in Salesforce?
Apex can be invoked by using triggers. Apex triggers enable you to perform custom actions before or after changes to Salesforce records, such as insertions, updates, or deletions.
Is it possible to create a contact lookup field trigger?
I would like to write a trigger whereby the user can enter the name of a Contact via a lookup field and the Contact's address and phone number will be automatically displayed in textfields. Please help. Thank you. No that is not possible trigger will only work after you perform any dem activity. In your case insert or update.
How do you update a field in a trigger in Salesforce?
Navigate to Setup ->Build ->Customize ->Contacts ->Triggers....update upAccList;Now, click on 'Save' button to save the trigger.In this way, we can create a trigger on Contact to update a field on Account.As the trigger is created, I'll be testing this by creating a new contact and updating a contact.More items...•
How do I see triggers in Salesforce?
To view the details for a trigger, from Setup, enter Apex Triggers in the Quick Find box, then select Apex Triggers, then click the name of the trigger. You can also access the trigger details from the object management settings for an object.
Why after triggers are read only in Salesforce?
You are getting this error because you are in an after insert trigger and the records are read-only in that context as they have been written, but not committed, to the database. This kind of error occurs if you try to update lists/record which are/is read-only in the trigger execution. For example, trigger.
How do I query a related list in Salesforce?
You can use a subquery: SELECT Id, Name, (SELECT Id, Name FROM Approvers__r) FROM opportunity. In Visualforce pages with a standard controller, you can use the apex:relatedList component to automatically show the list as it would have shown in the page layout.
What are the context variables of triggers?
Trigger Context VariablesVariableUsageisDeleteReturns true if this trigger was fired due to a delete operation, from the Salesforce user interface, Apex, or the API.isBeforeReturns true if this trigger was fired before any record was saved.isAfterReturns true if this trigger was fired after all records were saved.9 more rows
Can a trigger call a batch class?
Batch Apex can be invoked using an Apex trigger. But the trigger should not add more batch jobs than the limit.
What is before trigger and after trigger in Salesforce?
Before triggers are used to update or validate record values before they're saved to the database. After triggers are used to access field values that are set by the system (such as a record's Id or LastModifiedDate field), and to affect changes in other records. The records that fire the after trigger are read-only.
How can you avoid maximum trigger depth exceeded?
To avoid these kind of situation we can use public class static variable. We can solve this issue, you can set a condition on trigger so it will not be called recursively.
What is the order of execution in Salesforce?
What is Order of Execution in Salesforce? A set of rules that describe the path a record takes through all automations and the events that happen from SAVE to COMMIT. Before Salesforce executes these events on the server, the browser runs JavaScript validation if the record contains any dependent picklist fields.
How do I query a owner field in Salesforce?
SOQL: Accessing the Contact Owner FieldSELECT Contact.Owner, Contact.Name, Contact.Rule_Class__c.^ERROR at Row:1:Column:8.No such column 'Owner' on entity 'Contact'. If you are attempting to use a custom field, be sure to append the '__c' after the custom field name.
How do I query data in Salesforce?
Salesforce – Viewing Data in the Developer ConsoleAll of the object's fields display. Select the fields you would like displayed in the result list. ... Click the Query button to create and add the SOQL query to the editor.Click the Execute button to run the query and see the results.
How do I compare two field values in SOQL?
Salesforce does not allow direct field to field comparison in SOQL query. To achieve this you can create a formula field that will compare fields and return a value (such as true or false) which you can use in a WHERE clause.
What is trigger in Salesforce?
Apex triggers enable you to perform custom actions before or after changes to Salesforce records, such as insertions, updates, or deletions. A trigger is Apex code that executes before or after the following types of operations: insert. update. delete.
What is read only trigger?
The records that fire the after trigger are read-only. Triggers can also modify other records of the same type as the records that initially fired the trigger. For example, if a trigger fires after an update of contact A , the trigger can also modify contacts B, C, and D.
Why do callouts have to be asynchronous?
Callouts must be made asynchronously from a trigger so that the trigger process isn’t blocked while waiting for the external service's response. The asynchronous callout is made in a background process, and the response is received when the external service returns it.
When do upsert triggers fire?
upsert triggers fire both before and after insert or before and after update triggers as appropriate. merge triggers fire both before and after delete for the losing records, and both before and after update triggers for the winning record. See Triggers and Merge Statements.
What happens to triggers after a record is undeleted?
Triggers that execute after a record has been undeleted only work with specific objects. See Triggers and Recovered Records. Field history is not recorded until the end of a trigger. If you query field history in a trigger, you don’t see any history for the current transaction.
Can you undelete a trigger?
For example, you can have a trigger run before an object's records are inserted into the database, after records have been deleted, or even after a record is restored from the Recycle Bin.
