anchor.diff:            DELETE FROM mysql.user WHERE user = ''';
             FLUSH PRIVILEGES;
           '';
  -        services.mysql.ensureDatabases = [ "testdb" ];
  +        services.mysql.ensureDatabases = [ "testdb" "testdb2" ];
           services.mysql.ensureUsers = [{
             name = "testuser";
             ensurePermissions = {
               "testdb.*" = "ALL PRIVILEGES";
  +          };
  +        } {
  +          name = "testuser2";
  +          ensurePermissions = {
  +            "testdb2.*" = "ALL PRIVILEGES";
             };
           }];
           services.mysql.package = pkgs.mariadb;
  
positive.code:     mariadb.succeed(
          "echo 'use testdb; insert into tests values (42);' | sudo -u testuser mysql -u testuser"
      )
      mariadb.succeed(
          "echo 'use testdb; select test_id from tests;' | sudo -u testuser mysql -u testuser -N | grep 42"
      )
  
negative.code: 
        {
          users.users.testuser = { };
          users.users.testuser2 = { };
          services.mysql.enable = true;
          services.mysql.initialScript = pkgs.writeText "mariadb-init.sql" ''
            ALTER USER root@localhost IDENTIFIED WITH unix_socket;
  