Hi DJ,
First of all Thanks for the amazing content on odata filter.

the filter query Categories?$filter=Products/$count lt 10 does not work and throws an error . I am running it via postman

this is my whole query
https://developer-challenge.cfapps.eu10.hana.ondemand.com/odata/v4/northbreeze/Categories?$filter=Products/$count lt 10

Is there any changes in the filters ??
{
"error": {
"code": "500",
"message": "/An association can't be used as a value in an expression/"
}
}

Asked in Episode 3 https://youtu.be/Bln2A0_OauY?t=700

Hello DJ, I was wondering how would it be possible to integrate mutators (e.g. a bound action) to specific roles inside JWT tokens. is there a way to simplify the access control mapping the functions/actions to specific roles and finally JWT?

What they are, how they're defined and consumed

In the README.md, section Getting started, the user is advised:

After cloning this repo and moving into the repo top directory, first deploy to a local SQLite database and then start the service up:

cds deploy --to sqlite
cds run

May I suggest adding npm install to the bash commands, so the required packages are installed?

How to do this, what we need to configure, etc.

In Back to basics: OData - the Open Data Protocol - Part 2 - Basic operations, specifically at this point in the conversation, Andrew asked if it was possible to "hard code a filter in the path".

In today's episode, there was a question at around 58:30 about applying the system query option $filter to multiple levels in an $expand request, and whether it is possible. The context was this OData resource URL:

http://localhost:4004/northwind-model/Categories?$expand=Products($filter=Discontinued eq true)

and the wording of the question was: "can we combine filter on both Categories and Products entity set?".

The answer is: yes.

Here's an example (based on the CAP-based OData service defined in this repository) that uses the Suppliers entity set instead of the Categories entity set simply because there's more data for us with which to find a meaningful filter example.

If we want to retrieve the suppliers in the UK, and, alongside the supplier information itself, want a list of their products, but only products that have low stock (say, 15 units or fewer), we could ask for all of this in a single OData query operation thus:

http://localhost:4004/northwind-model/Suppliers
?$filter=Country eq 'UK'
&$expand=Products($filter=UnitsInStock le 15)

There are two filters at work here, one on the Suppliers entity set, and one on the Products entity set (remember that there's a managed association in the schema linking a supplier to their products).

This results in a JSON representation of that resource, that looks like this:

{
  "@odata.context": "$metadata#Suppliers(Products())",
  "value": [
    {
      "SupplierID": 1,
      "CompanyName": "Exotic Liquids",
      "ContactName": "Charlotte Cooper",
      "ContactTitle": "Purchasing Manager",
      "Address": "49 Gilbert St.",
      "City": "London",
      "Region": "NULL",
      "PostalCode": "EC1 4SD",
      "Country": "UK",
      "Phone": "(171) 555-2222",
      "Fax": "NULL",
      "HomePage": "NULL",
      "Products": [
        {
          "ProductID": 3,
          "ProductName": "Aniseed Syrup",
          "QuantityPerUnit": "12 - 550 ml bottles",
          "UnitPrice": 10,
          "Category_CategoryID": 2,
          "Supplier_SupplierID": 1,
          "UnitsInStock": 13,
          "UnitsOnOrder": 70,
          "ReorderLevel": 25,
          "Discontinued": false
        }
      ]
    },
    {
      "SupplierID": 8,
      "CompanyName": "Specialty Biscuits Ltd.",
      "ContactName": "Peter Wilson",
      "ContactTitle": "Sales Representative",
      "Address": "29 King's Way",
      "City": "Manchester",
      "Region": "NULL",
      "PostalCode": "M14 GSD",
      "Country": "UK",
      "Phone": "(161) 555-4448",
      "Fax": "NULL",
      "HomePage": "NULL",
      "Products": [
        {
          "ProductID": 21,
          "ProductName": "Sir Rodney's Scones",
          "QuantityPerUnit": "24 pkgs. x 4 pieces",
          "UnitPrice": 10,
          "Category_CategoryID": 3,
          "Supplier_SupplierID": 8,
          "UnitsInStock": 3,
          "UnitsOnOrder": 40,
          "ReorderLevel": 5,
          "Discontinued": false
        },
        {
          "ProductID": 68,
          "ProductName": "Scottish Longbreads",
          "QuantityPerUnit": "10 boxes x 8 pieces",
          "UnitPrice": 12.5,
          "Category_CategoryID": 3,
          "Supplier_SupplierID": 8,
          "UnitsInStock": 6,
          "UnitsOnOrder": 10,
          "ReorderLevel": 15,
          "Discontinued": false
        }
      ]
    }
  ]
}

I tried to follow your instructions of your youtube video for VS code "cds deploy --to sqlite", but it returns with error: cds : File C:\Users\XXXXX\AppData\Roaming\npm\cds.ps1 cannot be loaded. The file C:\Users\XXXXX\AppData\Roaming\npm\cds.ps1 is not digitally signed. You cannot run this script on the current system.
For more information about running scripts and setting execution policy, see about_Execution_Policies at https:/go.microsoft.com/fwlink/?LinkID=135170.
At line:1 char:1

• cds deploy --to sqlite
• CategoryInfo : SecurityError: (:) [], PSSecurityException
• FullyQualifiedErrorId : UnauthorizedAccess

I tried to google, but did not found a working solution, will you know why? thanks Sam

The OSPO bot created this issue by mistake - It did not have enough priviledge to check the vulnerability alerts, So I am closing this issue now. Sorry for any inconvenience.

For example, where does the @odata.context property come from?