Asp.net core - Entity Framework core - add additional data to a view object while keeping it a Query-CodePudding

    [EnableQuery]
    public ActionResult<IQueryable<OurView>> GetInteractionRecordings(int pageNumber)
    {
        IQueryable<OurView> ourViews = _dbContext.OurView
            .Skip((pageNumber - 1) * 100)
            .Take(100)
            .AsQueryable();

        // One of the fields in OurView is a PhotoPath (string) that's not in the database.
        // We want to add that PhotoPath to every row without enumerating (function call for each row)
        // As we want to keep it a queryable

        return Ok(ourViews);
    }

Regardless of the solution, most importantly, what we want to avoid is the following:

Let's assume there are 500,000 records in the database table, enumerating all these records in the table before executing "Take" or the PhotoPath lookups.

We want it as a Queryable as we are utilizing Odata.

CodePudding user response：

You can do that via Select:

var ourViews = _dbContext.OurView
    .Skip((pageNumber - 1) * 100)
    .Take(100);

var photoPath = "SomePath";

var withAdditionalData = ourViews
    .Select(x => new 
    {
        Id = x.Id,
        // other fields

        PhotoPath = photoPath
    });