To search with CQL in the file heijden.pgn:

1. Open VisualCQL.exe
2. Write the CQL keywords (see articles)
3. Press the button with a running man to start search.

The found matches are stored in the file result.pgn. 

The file heijden.pgn in the folder contains 664 studies awarded in 2020. 
The file result.pgn in the folder contains 95 stalemate studies found in the heiden.pgn using one keyword :stalemate
(position
:stalemate
)

You can replace the file heijden.pgn with any PGN file (name it heijden.pgn) to search in this file. 
Or you can add to the folder any PGN file with different name. To make a search in it you have to give its name in VisualCQL window (2nd line).

*************************************************************************************

    CQL   heijden.pgn:

1.  VisualCQL.exe.
2.    CQL (. )
3.     ,   .

     result.pgn.

 heijden.pgn    664 ,   2020 .
 result.pgn    95  ,    heiden.pgn     :stalemate.
(positiom
:stalemate
)

    heijden.pgn    PGN (  heijden.pgn)     .
        PGN   .           VisualCQL (2- ). 

