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LINQ Query with Conditional Joins Returning Unexpected Results in C#

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c# linq join csharp

Hey everyone, I'm running into an issue that's driving me crazy... I'm stuck trying to I'm sure I'm missing something obvious here, but I'm working with two collections in C# and trying to join them using LINQ based on a conditional logic, but I'm getting unexpected results..... I have a list of `Orders` and a list of `Customers`, and I want to join these lists such that I only get orders from customers who are active. However, the LINQ query is returning orders from inactive customers as well. Here are the relevant classes: ```csharp public class Order { public int OrderId { get; set; } public int CustomerId { get; set; } public decimal TotalAmount { get; set; } } public class Customer { public int CustomerId { get; set; } public string Name { get; set; } public bool IsActive { get; set; } } ``` I have the following lists: ```csharp List<Order> orders = new List<Order> { new Order { OrderId = 1, CustomerId = 1, TotalAmount = 100 }, new Order { OrderId = 2, CustomerId = 2, TotalAmount = 200 }, new Order { OrderId = 3, CustomerId = 3, TotalAmount = 300 } }; List<Customer> customers = new List<Customer> { new Customer { CustomerId = 1, Name = "Alice", IsActive = true }, new Customer { CustomerId = 2, Name = "Bob", IsActive = false }, new Customer { CustomerId = 3, Name = "Charlie", IsActive = true } }; ``` And here is my LINQ query: ```csharp var result = from order in orders join customer in customers on order.CustomerId equals customer.CustomerId where customer.IsActive select new { order.OrderId, customer.Name, order.TotalAmount }; ``` Despite the conditional filtering by `IsActive`, the result still includes orders from inactive customers. I've tried checking if the `IsActive` property is set correctly, and everything seems fine. I also tried switching to method syntax: ```csharp var result = orders.Join(customers, order => order.CustomerId, customer => customer.CustomerId, (order, customer) => new { order, customer }) .Where(joined => joined.customer.IsActive) .Select(joined => new { joined.order.OrderId, joined.customer.Name, joined.order.TotalAmount }); ``` But I continue to receive orders from inactive customers. Is there something I’m missing or a common pitfall with conditional joins in LINQ? Any insights would be appreciated! How would you solve this? I'm coming from a different tech stack and learning Csharp. What am I doing wrong? I recently upgraded to Csharp latest. Any feedback is welcome!