1.How to Store multiple assests for participant in hyperledger composer - hyperledger

Question

Hi iam new to Blockchain .. please help with this.
1.I have customer participant should able to store multiple assests.
2. How to query all products of a customer
namespace demo
participant Customer identified by customerId {
o String customerId
o String firstName
o String lastName
o String email
o String phone
o Address address optional
--> Product[] product optional // here i need to store multiple products that belongs to this customer
}
asset Product identified by productId{
o String productId
o productType producttype
o String productName
o String model
--> Customer owner optional
}

Answer 1

1-i think in your business case there is no meaning to add owner to each product because you already have array of assets(Products) which belongs to each Customer.
1.1-to save multiple assets in your product array this will be done in Transaction Processing Function in logic.js file
in the documentation link below you will find very useful information about how to implement it:
https://hyperledger.github.io/composer/latest/reference/js_scripts
1.2-as solution for query you are going to query this participant registry by the customerId and in the results you will find your array of products. as the following.
in the queries.qry file
query CurrentCustomer {
description: "Returns Certain Customer Details in This Registry"
statement:
SELECT demo.Customer
WHERE (customerId == _$customerId)
}
for better understanding about queries you can check the documentation link below:
https://hyperledger.github.io/composer/latest/tutorials/queries
2-the question here are you going to add new products to this array each time the customer will buy Product ?
so imagine your customer have bought 10,000 products and with multiple Customer with this rate your application performance will not be the best because retrieving this much of data and mutate it then update your participant(Customer).
you can instead build relation between customer and invoice and each invoice contains enum of Product will be represented as concept which will contains all product properties and in this case each invoice will have owner so you can query all invoices for certain customer.