Here's my question on custom big object: can we filter a record under big object?. I just want to filter and show an account record based on account name, here we are storing about 300,000 records of some custom object.
Yes, you can perform a SOQL query against a BigObject table. However, there are very significant limitations as to how you can construct your query.
The true answer to your question is going to ride on how your BigObject is defined. That's because the specific fields, and their order, in the BigObject's index defines how you can use standard SOQL against it.
If you're working with a BigObject
Order__b and it has an
Order_Number__c field that is the first field in its index, you can query using
WHERE Order_Number__c = :SOME_ORDER_NUMBER, for example.
If you want to do something more than that, you'd need to use Async SOQL to filter a dataset into a new custom object that you can then operate upon.