Populate two table data using ASP.NET Core - sql-server

Question

I want to get two table data in ASP.NET Core. I can get one table detail by using model class. then I can show data by using below code.
[HttpGet]
public async Task<ActionResult<IEnumerable<OrderMaster>>> GetOrderDetails()
{
return await _context.OrderDetails.ToListAsync();
}
So my question is how to get two tables data to the above method? As a example I want to retrieve data for below query:
select a.ItemDescription,a.Quantity,a.Amount, a.CustomerCode, b.CustomerName,b.CustomerAddress,b.MobileNumber,b.Email from OrderDetails as a left join CustomerDetails as b ON a.CustomerCode=b.CustomerCode
Thank you
My model classes
public class CustomerMaster
{
[Key]
public int CustomerCode { get; set; }
[Column(TypeName = "nvarchar(100)")]
public string CustomerName { get; set; }
[Column(TypeName = "nvarchar(100)")]
public string CustomerAddress { get; set; }
[Column(TypeName = "nvarchar(10)")]
public string MobileNumber { get; set; }
[Column(TypeName = "nvarchar(100)")]
public string Email { get; set; }
}
public class OrderMaster
{
[Key]
public int OrderId { get; set; }
[Column(TypeName = "nvarchar(100)")]
public string ItemCode { get; set; }
[Column(TypeName = "nvarchar(100)")]
public string ItemName { get; set; }
[Column(TypeName = "nvarchar(MAX)")]
public string ItemDescription { get; set; }
[Column(TypeName = "nvarchar(100)")]
public string Quantity { get; set; }
[Column(TypeName = "nvarchar(100)")]
public string OrderDate { get; set; }
[Column(TypeName = "nvarchar(100)")]
public string Amount { get; set; }
[Column(TypeName = "nvarchar(100)")]
public string CustomerCode { get; set; }
}
this is my Context class
public class AppDbcontext : DbContext
{
public AppDbcontext(DbContextOptions<AppDbcontext> options) : base(options)
{
}
public DbSet<CustomerMaster> CustomerDetails { get; set; }
public DbSet<OrderMaster> OrderDetails { get; set; }
}
}

Answer 1

For how to join two tables,a simple demo you could follow:
var model = (from a in _context.CustomerDetails
join b in _context.OrderDetails
on a.ID equals b.ID
select new {
Name = a.Name,
Address = b.Address
}).ToList();
Update 1:
You use left join sql,you need change like below:
var model = (from a in _context.OrderDetails
join b in _context.CustomerDetails
on a.CustomerCode equals b.CustomerCode.ToString() into ab
from b in ab.DefaultIfEmpty()
select new
{
ItemDescription = a.ItemDescription,
Quantity = a.Quantity,
Amount = a.Amount,
CustomerCode = a.CustomerCode,
CustomerName = b.CustomerName,
CustomerAddress = b.CustomerAddress,
MobileNumber = b.MobileNumber,
Email = b.Email,
}).ToList();
Update 2:
For how to return the two tables data,I think a better way is to create a view model to display:
public class OrderDetailViewModel
{
public string ItemDescription { get; set; }
public string Quantity { get; set; }
public string Amount { get; set; }
public string CustomerCode { get; set; }
public string CustomerName { get; set; }
public string CustomerAddress { get; set; }
public string MobileNumber { get; set; }
public string Email { get; set; }
}
[HttpGet]
public IEnumerable<OrderDetailViewModel> GetOrderDetails()
{
var model = (from a in _context.OrderDetails
join b in _context.CustomerDetails
on a.CustomerCode equals b.CustomerCode.ToString() into ab
from b in ab.DefaultIfEmpty()
select new OrderDetailViewModel
{
ItemDescription = a.ItemDescription,
Quantity = a.Quantity,
Amount = a.Amount,
CustomerCode = a.CustomerCode,
CustomerName = b.CustomerName,
CustomerAddress = b.CustomerAddress,
MobileNumber = b.MobileNumber,
Email = b.Email,
}).ToList();
return model;
}

Answer 2

You have to get the two models connected through navigation properties. Something like
public class Table1 {
int Table1Id;
string Name;
ICollection<Table2> Tables2;
}
public class Table2 {
int Table2Id;
string Address;
Table1 Table1;
}
Then you can have your business layer code
[HttpGet]
... GetNameWithAddresses(int id) {
return (from c in _context.Table1 where c.Table1Id == id
select new { c.Name, c.Tables2 }).ToList();
}
If the tables have primary-foreign key relationship, it will be done automatically for you if you scaffold them. And if you don't have FK relationship, you have to ask yourself why!

Answer 3

Use this code
using (var context = new AppDbcontext())
{
var table1 = context.CustomerDetails.ToList();
var table2 = context.OrderDetails.ToList();
}