What is the recommended solution for exporting 40 million Account records while encountering a full table scan time-out failure?

The recommended solution for exporting 40 million Account records that are encountering a full table scan time-out failure is to modify the export job header to specify Sforce-Enable-PKChunking. This approach leverages primary key chunking, a method designed to optimize the retrieval of large data sets in Salesforce. By splitting the export process into smaller, more manageable pieces based on primary key ranges, it reduces the load on the database and minimizes the likelihood of time-out issues during the export.

This technique is particularly beneficial for large data exports as it allows for parallel processing of data, making the operation more efficient. As the system processes chunks of records sequentially or in parallel rather than attempting to handle the entire dataset at once, it helps in circumventing potential performance bottlenecks associated with scanning extensive records in a single go.

While alternatives such as adjusting the query or setting batch sizes may provide some relief, they do not target the underlying issue of the time-out experienced during a full table scan. The essence of Sforce-Enable-PKChunking lies in its ability to efficiently segment the data based on primary keys, thus enhancing the export operation's overall success.