Consider the LoyaltyCard database DTO I have below:
[Alias("customer_ids")]
[CompositeIndex("id_code", "id_number", Unique = true)]
public class LoyaltyCard
{
[Alias("customer_code")]
public int CustomerId { get; set; }
[Alias("id_code")]
public string LoyaltyCardCode { get; set; }
[Alias("id_number")]
public string LoyaltyCardNumber { get; set; }
[Alias("date_issued ")]
public DateTime? IssueDate { get; set; }
[Alias("linked_id")]
public bool LinkedId { get; set; }
[Alias("positive_id")]
public bool PositiveId { get; set; }
}
I have CustomerId as a property because I need it to be included in the WHERE clause of the generated SQL, but I don't want the column to also be selected in the result set. Is there a way to include it in the where but exclude it from the select?
// I was hoping that result would not have a populated CustomerIds
var result = db.Select<LoyaltyCard>(id => id.LoyaltyCardCode == "PS" && id.CustomerId == customerCode);
I've tried adding the [Ignore] attribute but that fails with SqlException: Invalid column name 'CustomerId'.
If you don't want the entire POCO populated you'd need to specify a Custom Select with just the fields you want selected, e.g:
var result = db.Select<LoyaltyCard>(db.From<LoyaltyCard>()
.Where(id => id.LoyaltyCardCode == "PS" && id.CustomerId == customerCode)
.Select(x => new {
x.LoyaltyCardCode,
x.LoyaltyCardNumber,
x.IssueDate,
x.LinkedId,
x.PositiveId
}));
Related
I'm having an issue with a series of Include/ThenInclude in a query.
Here is my EntityFrameworkCore Query :
var fund = await funds.Where(x => x.Id == fundId)
.Include(f => f.Compositions.Where(compo => compo.Date == compositionDate))
.ThenInclude(c => c.CompositionItems)
.ThenInclude(item => item.Asset)
.FirstOrDefaultAsync(token)
?? throw new NotFoundException(nameof(Fund), fundId);
I recieve a 'CompositionDate does not exists' error.
As you can see the CompositionDate property is at the Compositions Level.
When I check the SQL generated I get this in a subquery Select statement :
SELECT f1."CompositionFundId", f1."CompositionDate", f1."AssetId", f1."Amount", a."Id", a."CountryCode", a."Currency", a."FundCompositionDate", a."FundCompositionFundId", a."Isin", a."Name", a."SecurityType", a."Ticker", a."Coupon", a."GicsSector", a."InvestmentCase", a."IpoDate", a."Theme"
FROM "FundCompositionItem" AS f1
INNER JOIN "Asset" AS a ON f1."AssetId" = a."Id"
Those 2 properties a."FundCompositionDate", a."FundCompositionFundId" doesn't exists at the 'Asset' level.
They exists in the parent (at the 'Where' level on the first Include).
I'm using Postgres provider for EFcore. Could this be the issue?
Should I be using the select anonymous type .Select(x => new { Fund = x, Compo = x.Compo.Where(...), etc... }?
I would like to preserve the navigation properties if possible. (accessing assets from compositionItems)
Any help would be much appreciated.
Edit:
Models as requested by Atiyar:
public class Portfolio : AuditableEntity
{
public Guid Id { get; set; }
public Guid Name{ get; set; }
}
public class Fund : Portfolio
{
// Irrelevant properties
public IList<FundComposition> Compositions { get; } = new List<FundComposition>();
}
public class FundComposition
{
public Fund Fund { get; set; }
// Primary key / Foreign key
public Guid FundId { get; set; }
// Primary Key
public DateTime Date { get; set; }
public List<FundCompositionItem> CompositionItems { get; set; } = new();
}
public class FundCompositionItem
{
public FundComposition Composition { get; set; }
// Primary Key
public Guid CompositionFundId { get; set; }
// Primary Key
public DateTime CompositionDate { get; set; }
public Asset Asset { get; set; }
// Primary Key
public Guid AssetId { get; set; }
public double Amount { get; set; }
}
public class Asset : BaseEntity
{
// Primary Key
public Guid Id { get; set; }
public string Name { get; set; }
public string Currency { get; set; }
// more properties
}
In my experience, I've applied the Include() and ThenInclude() first and then applied the any conditional clauses afterwards. I'm also not sure if using Where inside of an include method does what you expect it to.
You can also apply your conditional in the first parameter of .FirstOrDefaultAsync().
var fund = await funds.Where(x => x.Id == fundId)
.Include(f => f.Compositions)
.ThenInclude(c => c.CompositionItems)
.ThenInclude(item => item.Asset)
.FirstOrDefaultAsync(x =>
x.Id == fundId && x.Compositions.Any(compo => compo.Date == compositionDate),
token
)
Using C# MVC5 Visual studio 2015.
I have a method that contains the following code:
public List<OffersOnPropertyViewModel> Build(string buyerId)
{
var filtered = _context.Properties.Where(x => x.Offers.Any(c => c.BuyerUserId == buyerId)).ToList();
var model = filtered.Select(c =>
{
var item = new OffersOnPropertyViewModel()
{
PropertyType = c.PropertyType,
NumberOfBedrooms = c.NumberOfBedrooms,
StreetName = c.StreetName,
Offers = c.Offers.Where(d => d.BuyerUserId == buyerId).Select(x => new OfferViewModel
{
Id = x.Id,
Amount = x.Amount,
CreatedAt = x.CreatedAt,
IsPending = x.Status == OfferStatus.Pending,
Status = x.Status.ToString(),
BuyerUserId = x.BuyerUserId
}),
};
return item;
}).ToList();
//TODO: refactor, shorten linq, duping where clause
return model;
}
Here is the model:
public class Property
{
[Key]
public int Id { get; set; }
[Required]
public string PropertyType { get; set; }
[Required]
public string StreetName { get; set; }
[Required]
public string Description { get; set; }
[Required]
public int NumberOfBedrooms { get; set; }
[Required]
public string SellerUserId { get; set; }
public bool IsListedForSale { get; set; }
public ICollection<Offer> Offers { get; set; }
}
In the DB Offers table has the property id as its FK.
The method fails at runtime saying the Value cannot be null.
When I step through I notice the filtered results (in the example its 1 result), is saying offers is null. Although the query just filtered the results based on "x.Offers".
I simply need a way to retrieve a list of property's that have offers made by the buyerId provided. Is my approach wrong? or am i missing a one liner?
Thanks
You will need to add Include() to your LINQ query to bring in child objects, as follows:
var filtered = _context.Properties.Include("Offers")
.Where(x => x.Offers.Any(c => c.BuyerUserId == buyerId)).ToList();
The reason your filter works with the Any() is because when generating the SQL query, this part forms the WHERE clause and is not included in the SELECT.
I want to retreive LineOfBusiness property from promotionCatalogResponseRootObject where PromotionID is equal to myId
public class PromotionCatalogResponseRootObject
{
public PromotionCatalogResponse PromotionCatalog { get; set; }
}
public class Promotion
{
public string PromotionId { get; set; }
public string LineOfBusiness { get; set; }
public string PromotionName { get; set; }
}
public class PromotionCatalogResponse
{
public List<Promotion> Promotion { get; set; }
}
I started off like this but I know I'm doing it wrong. Please guide
string myId = "7596";
string lineOfBusiness = dataPromotionCatalog.PromotionCatalog
.Promotion.Find(p => p.LineOfBusiness);
What you are missing is the the Find method is expecting to receive a predicate with a bool return value but you are returning a string, the LineOfBusiness property.
First filter the items you want and then select the desired property. In addition, I'd go with the Where instead of the Find. (Find() vs. Where().FirstOrDefault())
var result = dataPromotionCatalog.PromotionCatalog.Promotion
.Where(i => i.PromotionId == myId)
.Select(i => i.LineOfBusiness);
or in query syntax
var result = (from item in dataPromotionCatalog.PromotionCatalog.Promotion
where item.PromotionId == myId
select item.LineOfBusiness);
If you are expecting/want to have one item then use FirstOrDefault:
var result = dataPromotionCatalog.PromotionCatalog.Promotion
.FirstOrDefault(i => i.PromotionId == myId)?.LineOfBusiness;
I'm trying to use a calculated value in my OrderBy clause in a LINQ query.
The error I am getting is:
DbArithmeticExpression arguments must have a numeric common type.
My model looks like this:
public class PostModel
{
public int ID { get; set; }
public DateTime Created { get; set; }
public string Title { get; set; }
public string Description { get; set; }
public string FilePath { get; set; }
public float Rank { get; set; }
public UserProfile Creator { get; set; }
public bool ShowPost { get; set; }
public PostModel()
{
Created = DateTime.Now;
Rank = 0;
ShowPost = false;
}
}
and I'm trying to select posts using this:
var todaysDate = DateTime.Now.AddDays(-10);
var result = _database.Posts
.Where(p => p.ShowPost == true)
.OrderBy(x => ((float)x.Rank) - (((float)(x.Created - todaysDate).TotalDays)) / 2f)
.Skip(page * StaticVariables.ResponseDataPageSize)
.Take(StaticVariables.ResponseDataPageSize)
.Select(s => new
{
id = s.ID,
rank = s.Rank,
title = s.Title,
description = s.Description
}
);
It's the order by causing the error. I first thought it was that I was not casting all my variables to the same type, but adding (float) does not seem to help.
The purpose of the code is to make make high ranking posts fall down the list over time as to allow newer information to be shown.
Any ideas?
Use EntityFunctions in LinqToEntity:
EntityFunctions.DiffDays(todaysDate, x.Created)
I am using RavenDb in C# web project. I have an object that I need to query its child collection with 1 row per child object and some of the root/parent object properties.
Note: This is not the actual design, just simplified for this question.
public class OrderLine
{
public string ProductName { get; set; }
public int Quantity { get; set; }
public DateTime? ShipDate { get; set; }
}
public class Order
{
public int OrderId { get; set; }
public string CustomerName { get; set; }
public DateTime OrderDate { get; set; }
public List<OrderLine> OrderLines { get; set; }
}
The order with the orderlines is one single document. ShipDate will be updated on each line because not all products are always in stock.
I need to be able to create a list of the last 10 products sent with the following columns:
OrderId
Customer
ProductName
ShipDate
This doesn't work because SelectMany is not supported:
var query = from helper in RavenSession.Query<Order>()
.SelectMany(l => l.OrderLines, (order, orderline) =>
new { order, orderline })
select new
{
helper.order.OrderId,
helper.order.CustomerName,
helper.orderline.ProductName,
helper.orderline.ShipDate
};
var result = query.Where(x => x.ShipDate.HasValue)
.OrderByDescending(x => x.ShipDate.Value).Take(10);
I believe the right thing to do isto create an Index that will flatten out the list but I haven't had any success. I don't believe a Map-Reduce situation will work because as I understand it will effectively does a group by which Reduces the number of documents to less rows (in the index). But in this case, I am trying to expand the number of documents to more rows (in the index).
I would rather not put each OrderLine in a separate document but I do not know what my options are.
Since you want to filter and sort by fields in the subclass, you'll need to make sure all the fields you want are indexed and stored.
public class ShippedItemsIndex
: AbstractIndexCreationTask<Order, ShippedItemsIndex.Result>
{
public class Result
{
public int OrderId { get; set; }
public string CustomerName { get; set; }
public string ProductName { get; set; }
public int Quantity { get; set; }
public DateTime ShipDate { get; set; }
}
public ShippedItemsIndex()
{
Map = orders =>
from order in orders
from line in order.OrderLines
where line.ShipDate != null
select new
{
order.OrderId,
order.CustomerName,
line.ProductName,
line.Quantity,
line.ShipDate
};
StoreAllFields(FieldStorage.Yes);
}
}
Then you can project from the index into your results.
var query = session.Query<Order, ShippedItemsIndex>()
.ProjectFromIndexFieldsInto<ShippedItemsIndex.Result>()
.OrderByDescending(x => x.ShipDate)
.Take(10);
var results = query.ToList();
Here is a complete test demonstrating.