In general, it is possible to read the data from every database that is supported by Excel for opening. The path to the source file cannot be set as a relative path (the "Settings" sheet, the "B1" cell). External databases (those that are supported) are opened in Excel by the "Open" method. And that's why it is normal that "Sheet name with source data" = File name without the extension (the "Settings" sheet, the "B2" cell). Settings of Excel must be done in the option:
If the sheet (book) is renamed, then the script (Makro) will fail.
The following process was used:
In "Sheet1" press the right mouse key on the blank field of the "Menu" bar and select control toolbox from the offered items.
In the "Control toolbox" box press the "Design mode" button to become active, and then "Command button".
Then mark the area in the sheet by the mouse with the pressed left key into which the button is drawn. By the right mouse key on this object, the appearance and the descriptive text can be adjusted in the properties. By double-clicking the object, "Visual Basic Editor" is called and there the "function is preset" that is called after pressing the key (described below). Close "Visual Basic Editor", close the design mode (deactivate by pressing the button) and save the application.
Description of Editor and its basic functions:
All sheets of the application are available in the "Project-VBAProject" window (Project Explorer button), then the "ThisWorkbook" object and "Module1" in the Modules section. After double-clicking the object, the content (scripts) of these objects appears in the edit window. This application has created the function in the "ThisWorkbook" object of the "Open" event that is called in the moment when the application is opened. (It calls the "Init" function in global "Module1" and the event is operated at the same time if this function fails).
In the "Sheet1" object there is a list of functions that are sequentially called if "Button" is pressed in this sheet. The event is again operated if any of the functions fails.
And in the "Module1" object there are functions that are referenced after pressing a button or those that control run of the started process.
Global variables are created in the opening (Public - these are accessible in all functions and objects of this application).
Help in Visual Basic Editor is called by the F1 key, it is functional even by context if the cursor is placed on the key word.
Functions can be executed one by one if the cursor is placed in the body of the function and the "Run Sub/User Form" button is activated or by the F5 key.
The script can be executed step-by-step by the "Step Into" key.
The execution of the script is stopped by the "Reset" button.
The breakpoint of the script execution is created on the point where the cursor is placed after pressing the "Toggle Breakpoint" button.
The value of the variable can be watched in the Watch window that is started by the "Watch" button. The required variable whose value can be then watched is moved into it by dragging the mouse during the "step-by-step" execution.