This is a simple database-tool for copy the values from the collection of documents from the source database to the determinate fields of the document from the collection of documents from the target database.
Source and target collections are compared by a key (it takes from "evaluate key").

Example. You have two databases: the Test and the Work. Users typed some real data into documents of the Test database. And you want to copy only some fields to the fit documents to the Work database.
In this tool you:
1)    point source (the Test) database (server, path, view), evaluate key (for comparing) and evaluate text (for displaying), push "extract data"
2)    point target database (the Work), push "extract data"
3)    push "compare" for comparing collections
4)    detect table of fields (push "add" and type field and type evaluate value)
5)    push "update"

This tool is not for big data, for about 1-2 hundred documents.
(In this database you can create 1000 temp documents for demonstration of working. And this must work quickly)

This is not genius tool, of course. But may be for newbie programmer will be interesting. We use only javascript (two libraries: one server side and one client side) and most of data we contain in scope-variables. And this is the real working tool.