Do you ever wonder which Apex Class is more efficient for processing records?
As Salesforce developers, we use Batch Apex Class to process large numbers of records, while the Future method is used for executing long-running operations asynchronously. But when we need to have both the operations of the Batch and Future method, we should implement the Queueable Interface.
So, in this blog, we will bring forth the key differences between Batch Apex and Queueable Apex Class for you to reckon with the most efficient one.
What is Batch Apex
We Know Batch Apex is used to run large jobs that would exceed normal processing units. Using Batch apex, we can process records asynchronously in batches and process up to 50million records in the background, unlike Future and Queueable.
Batch Apex Syntax
Code
Batch apex methods:
Start().
Execute().
Finish().
How Batch Apex Works
Start(): query all records : lets say 100000 [Sends 2000 records every time(Maximum BatchSize)].
Execute(): going to process 20000 records only.
Finish(): Post-Processing and other tasks like sending mail or handling exception
Batch Size
Minimum batch size – 1
Maximum batch size – 2000
Default will be – 200
Way of Calling:
Code
Limitations of Batch Apex
- Can have only 5 batch jobs running at a time.
- Execution may be delayed due to server availability.
- @Future methods are not allowed.
- Future methods cannot be called from Batch Apex.
Reasons to use Batch Apex over Queueable
- It allows the processing of 50million of records in the background
- Best suitable for long-running processes
What is Queueable Apex Salesforce
Queueable Apex Salesforce is a more advanced and enhanced version of future methods with some extra features. It has the simplicity of future methods and the power of Batch Apex, combined to form Queueable Apex.
Queueable Apex Syntax
We need to implement Apex Class with Queueable Interface which contains only one method execute. We also need to implement DatabaseAllowsCallouts in case you want to process the callouts from the Queueable apex.
Code
Execute Queueable Apex
Execute the Queueable apex with System.enqueueJob method which will return the job Id. Once you enqueue a new job, you get a job ID that you can actually monitor from the ApexJobs sections or by using AsyncApexJob object.
Code
Limitations of Queueable Apex
There are some limitations of Queueable Apex Class.They are-
- Queueable can’t handle millions of records in one job.
- Only one job can be scheduled at a time.
- In the developer edition stack depth for chaining the jobs is limited to 5 including the parent job.
Reasons to use Queueable Apex over Batch Apex
- It is useful in operations that involve both Batch and Future methods.
- Queueable apex can be called from the Future and Batch class.
- Moreover Queueable apex supports getContent/getContentAsPDF () method.
- In Queueable apex, we can chain up to 50 jobs and in developer edition, we can chain up to 5 jobs only whereas in Batch Apex 5 concurrent jobs are allowed to run at a time.
- We can call a future method for executing long-running operations, such as callouts to external web services or other operations, on its own time as we can’t call future methods from the batch class.
Conclusion
We hope this blog helps you gauge how Batch Apex differs from Queueable Apex. Be sure to try out the solution and share your experience with us. Stay connected to our technical blogs to learn more about such interesting Salesforce development solutions. We’ll be back with another blog soon. Till then, Happy Learning!
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