How can I know number of records of All Salesforce Object?

Question

I have written a small Apex class to fetch list of all available (Standard+Custom) Objects in Org and their fields.

But when trying to retrieve total record of individual Object, this is showing too many SOQL issue. I understand this is happening due to the Query inside For{}. Is there any other way to fetch All Objects' total records.

Map<String, Schema.SObjectType> GlobalMap = Schema.getGlobalDescribe();         
        for (Schema.SObjectType Obj : GlobalMap.values()) {
            Schema.DescribeSObjectResult ObjDesc = Obj.getDescribe();
        system.debug(' Object Name   : ' + ObjDesc.getName()); 
        system.debug(' Object Fields : ' + ObjDesc.fields.getMap().keySet().size());    
        AggregateResult arRecs = Database.query('Select count(id) nRecs from '+ObjDesc.getName());
        system.debug(' Total Records : ' + Integer.valueOf(string.valueOf(arRecs.get('nRecs'))));               

            }
        }

Answer 1

You can use the Iterable interface to your rescue. Here's how you can do that -

1. Create a List with all the object API names you get from describe call
2. Do check if the object can be queried, only then add it to the list
3. Create a new batch class that implements Database.Batchable
4. Instead of returning a List like a normal batch would do, return Iterable from the start() method
5. Use the iterator (object API name) from your execute() method and query for that object
6. Store the count for this object somewhere for use in future method so as to send the email

Remember to implement Database.Stateful as well, since you'll have to maintain the state of counts of all the objects

A similar implementation is given as an example here - https://andyinthecloud.com/2013/08/11/batch-worker-getting-more-done-with-less-work/

Instead of using List<String> { 'Do something', 'Do something else', 'And something more' }; in the start method, form a list of all object API names.