Spreadsheet - How to save and load documents from a database

UPDATED:

Starting with v16.1, Spreadsheet provides the capability to handle certain actions in the Controller. So, it is possible to save a document to a database using the Spreadsheet ribbon's 'Save' button.

UPDATED:

This code example demonstrates how to save and restore Spreadsheet documents from a database using a Binary column.
Starting with version 15.1, it is possible to use the SpreadsheetExtension.Open method to load a document and call the SpreadsheetExtension.SaveCopy method to save changes.

For Older Versions:
Use ISpreadsheetComponent.LoadDocument to load a document and ISpreadsheetComponent.SaveDocument - to save it.

See also:
T190812: ASPxSpreadsheet - How to save and load documents from a database