SQLのエクスプレスクエリ

keynameを検討する およびRestaurantTimings テーブル名として。これを試してください：-

app.get('/RestaurantDesc/:Key',function(request,response,next){

    var keyName=request.params.Key;
    var name_of_restaurants, RestaurantTimings;

    async.series( [
        // Get the first table contents
        function ( callback ) {
            connection.query('SELECT * FROM ', keyName, function(err, rows, fields)
                {
                        console.log('Connection result error '+err);
                        name_of_restaurants = rows;
                        callback();
                });
        },
        // Get the second table contents
        function ( callback ) {
        connection.query('SELECT * FROM ', RestaurantTimings, function(err, rows, fields)

            {
                    console.log('Connection result error '+err);
                    RestaurantTimings = rows;
                    callback();
            });
        }

   // Send the response
], function ( error, results ) {
    response.json({
        'restaurants' : name_of_restaurants,
        'RestaurantTimings' : RestaurantTimings
    });
} );
} );