with the help of AI I wrote an Code that could read txt documents and format them into an exportable csv. Now I want the program to check if the current title can be found in the my_database.db and then copy the artists from the database in the csv. My Problem is that the artists aren’t being copied in the csv. I wrote the code in Rust.

This is an example of a line in the input.txt I load in the program:

KPM_KPM_0858_00101_SCARS_A_Matt_Black_Christian_J_O_Lundberg.mp3.new.01

Then the program parses this line into:

Index: KPM_KPM_0858_00101
Title: scars a
Artists: matt black christian j o lundberg

I want to check the database because in the databse the artists are seperated with an _, so I know when a new person begins.

the complete code is on GITHUB:
https://github.com/TJ-5/GEMA_RUST

If anyone could help me out it would be great! I tried a lot of things but I think this is exactly over my programming knowledge. I am new to programming and this is the first program in RUST so please don’t roast me 🙂

Thats the function that should do the scanning and copying:

fn apply_database_info(&mut self) {
        let Some(conn) = self.db_connection.as_ref() else {
            info!("Keine Datenbankverbindung vorhanden. Überspringe apply_database_info().");
            return;
        };
    
        // Prepare the query once
        let query = r#"
            SELECT kuenstler
            FROM tracks
            WHERE LOWER(REPLACE(titel, '_', '')) = LOWER(REPLACE(?1, '_', ''))
            LIMIT 1
        "#;
    
        let mut stmt = match conn.prepare(query) {
            Ok(s) => s,
            Err(e) => {
                info!("Fehler beim Vorbereiten der Abfrage: {}", e);
                return;
            }
        };
    
        // Iterate through all tracks and update artists from database
        for (_filename, tracks) in self.tracks_per_file.iter_mut() {
            for track in tracks.iter_mut() {
                let result = stmt.query_row(params![&track.titel], |row| {
                    row.get::<_, String>(0)
                });
    
                match result {
                    Ok(db_artist) => {
                        // Replace spaces with underscores in the artist name
                        let formatted_artist = db_artist.replace(" ", "_");
                        info!(
                            "Track '{}' gefunden, Künstler von '{}' zu '{}' aktualisiert", 
                            track.titel, 
                            track.kuenstler, 
                            formatted_artist
                        );
                        track.kuenstler = formatted_artist;
                    }
                    Err(_) => {
                        info!(
                            "Track '{}' nicht in der Datenbank gefunden, behalte Künstler '{}'", 
                            track.titel, 
                            track.kuenstler
                        );
                    }
                }
            }
        }
    }

in the csv I was expecting “matt black_christian j o lundberg” because thats the way it is written in the database. So the artists are seperated with an _. Not with a comma because that would create a problem because of the csv (Comma-separated values).