SQL Select a value from database

For a Discord bot I have a command that changes the prefix of that guild, it 'works fine' as in it updates it in my database (MySQL Workbench), but the commands still triggers for ANY prefix, so if you stick any character in-front of the command it triggers instead of the one in the database.

This is my code to check the prefix:

let prefix = "!"; 

connection.query(`SELECT * FROM guilds WHERE guildid = ${message.guild.id}`, (error, commands) => {
  if (error) throw error;

  if (commands.length) {  //guild exists in database
    commands.forEach(value => 
        prefix = value.prefix;
        console.log(value.prefix); // returns correct prefix from database
    });
  } else {
    prefix = "!";
  }
});

via Rusty