DevOps, CI/CD and Automation

Hello, I have a question and I can't find any solution in this forum, maybe someone can help me.

I have a Table: Documents in the database this includes, a DocumentID and the Document as a Blob.

Now I want to write a Skript that allows user to Download one of the Blobs from the Database via Internet.
The user should choose the dokument via a radiobutton and when he clicks on the submit button i want that the download starts via a download.php ( I hope you understand what I mean)

I have written a Stored Procedure ...
something like this

PROCEDURE Blob_return (DocumentID_in IN number, BLOB_out OUT NOCOPY BLOB) as

begin
select document into blob_out from documents
where dokumentID = DokumenteD_in;
end;
...

But how can i handle this Skript in PHP.

Thanxs for your help