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1

0

I have the following entities:

public class Order

 public int Id get; set; 
 public ICollection<LineItem> LineItems get; set; 


public class LineItem

 public int Id get; set; 
 public int Qty get; set; 

I would like to just check if an order has large items (qty > 50), so I would like to add a property to Order class like so:

public class Order

 public int Id get; set; 
 public ICollection<LineItem> LineItems get; set; 

 public bool HasLargeItems
 
 get
 
 return LineItems.Any(l => l.Qty > 50);
 
 

This however, doesn't work because of lazy-loading. But if I use .Include(o => o.LineItems), it will fetch all the LineItems and then do an in-memory comparison. I would rather have this generate and execute a query against the db and just get me back a boolean value.

Is this possible to do as a property of Order entity, or do I have to write some other external query object which uses DbContext to perform these kinds of checks?

c# entity-framework entity-framework-6

share|improve this question

edited Mar 8 at 4:59

Uwe Keim

27.7k32133215

asked Mar 8 at 4:57

RizRiz

2,467114678

add a comment | 

1

0

I have the following entities:

public class Order

 public int Id get; set; 
 public ICollection<LineItem> LineItems get; set; 


public class LineItem

 public int Id get; set; 
 public int Qty get; set; 

I would like to just check if an order has large items (qty > 50), so I would like to add a property to Order class like so:

public class Order

 public int Id get; set; 
 public ICollection<LineItem> LineItems get; set; 

 public bool HasLargeItems
 
 get
 
 return LineItems.Any(l => l.Qty > 50);
 
 

This however, doesn't work because of lazy-loading. But if I use .Include(o => o.LineItems), it will fetch all the LineItems and then do an in-memory comparison. I would rather have this generate and execute a query against the db and just get me back a boolean value.

Is this possible to do as a property of Order entity, or do I have to write some other external query object which uses DbContext to perform these kinds of checks?

c# entity-framework entity-framework-6

share|improve this question

edited Mar 8 at 4:59

Uwe Keim

27.7k32133215

asked Mar 8 at 4:57

RizRiz

2,467114678

add a comment | 

I have the following entities:

public class Order

 public int Id get; set; 
 public ICollection<LineItem> LineItems get; set; 


public class LineItem

 public int Id get; set; 
 public int Qty get; set; 

I would like to just check if an order has large items (qty > 50), so I would like to add a property to Order class like so:

public class Order

 public int Id get; set; 
 public ICollection<LineItem> LineItems get; set; 

 public bool HasLargeItems
 
 get
 
 return LineItems.Any(l => l.Qty > 50);
 
 

This however, doesn't work because of lazy-loading. But if I use .Include(o => o.LineItems), it will fetch all the LineItems and then do an in-memory comparison. I would rather have this generate and execute a query against the db and just get me back a boolean value.

Is this possible to do as a property of Order entity, or do I have to write some other external query object which uses DbContext to perform these kinds of checks?

c# entity-framework entity-framework-6

share|improve this question

edited Mar 8 at 4:59

Uwe Keim

27.7k32133215

asked Mar 8 at 4:57

RizRiz

2,467114678

public class Order

 public int Id get; set; 
 public ICollection<LineItem> LineItems get; set; 


public class LineItem

 public int Id get; set; 
 public int Qty get; set; 

public class Order

 public int Id get; set; 
 public ICollection<LineItem> LineItems get; set; 

 public bool HasLargeItems
 
 get
 
 return LineItems.Any(l => l.Qty > 50);
 
 

share|improve this question

edited Mar 8 at 4:59

Uwe Keim

27.7k32133215

asked Mar 8 at 4:57

RizRiz

2,467114678

share|improve this question

edited Mar 8 at 4:59

Uwe Keim

27.7k32133215

asked Mar 8 at 4:57

RizRiz

2,467114678

edited Mar 8 at 4:59

Uwe Keim

27.7k32133215

edited Mar 8 at 4:59

Uwe Keim

27.7k32133215

asked Mar 8 at 4:57

RizRiz

2,467114678

asked Mar 8 at 4:57

RizRiz

2,467114678

2 Answers
2

active

oldest

votes

0

One way to do this is using anonymous select

 var order = dbContext.Orders
 .Where(o => o.Id == id)
 .Select(o => new Order = o, HasLargeItems = o.LineItems.Count > 50 )
 .SingleOrDefault();

share|improve this answer

answered Mar 8 at 5:15

tiatia

7,98111939

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  I know how I can do this outside of the class. I am just asking if it's possible to do efficiently as a property of the entity without having access to dbContext.
  
  – Riz
  Mar 8 at 5:18
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Maybe not then.
  
  – tia
  Mar 8 at 5:20
  

  
  
  
  

add a comment | 

0

Try this it might help:

public bool HasItems
 
 getreturn LineItems.AsQueryable().Any(x => false);
 

share|improve this answer

answered Mar 8 at 5:29

neelesh bodgalneelesh bodgal

313

add a comment | 

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0

One way to do this is using anonymous select

 var order = dbContext.Orders
 .Where(o => o.Id == id)
 .Select(o => new Order = o, HasLargeItems = o.LineItems.Count > 50 )
 .SingleOrDefault();

share|improve this answer

answered Mar 8 at 5:15

tiatia

7,98111939

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  I know how I can do this outside of the class. I am just asking if it's possible to do efficiently as a property of the entity without having access to dbContext.
  
  – Riz
  Mar 8 at 5:18
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Maybe not then.
  
  – tia
  Mar 8 at 5:20
  

  
  
  
  

add a comment | 

0

One way to do this is using anonymous select

 var order = dbContext.Orders
 .Where(o => o.Id == id)
 .Select(o => new Order = o, HasLargeItems = o.LineItems.Count > 50 )
 .SingleOrDefault();

share|improve this answer

answered Mar 8 at 5:15

tiatia

7,98111939

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  I know how I can do this outside of the class. I am just asking if it's possible to do efficiently as a property of the entity without having access to dbContext.
  
  – Riz
  Mar 8 at 5:18
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Maybe not then.
  
  – tia
  Mar 8 at 5:20
  

  
  
  
  

add a comment | 

One way to do this is using anonymous select

 var order = dbContext.Orders
 .Where(o => o.Id == id)
 .Select(o => new Order = o, HasLargeItems = o.LineItems.Count > 50 )
 .SingleOrDefault();

share|improve this answer

answered Mar 8 at 5:15

tiatia

7,98111939

 var order = dbContext.Orders
 .Where(o => o.Id == id)
 .Select(o => new Order = o, HasLargeItems = o.LineItems.Count > 50 )
 .SingleOrDefault();

share|improve this answer

answered Mar 8 at 5:15

tiatia

7,98111939

answered Mar 8 at 5:15

tiatia

7,98111939

answered Mar 8 at 5:15

tiatia

7,98111939

0

Try this it might help:

public bool HasItems
 
 getreturn LineItems.AsQueryable().Any(x => false);
 

share|improve this answer

answered Mar 8 at 5:29

neelesh bodgalneelesh bodgal

313

add a comment | 

0

Try this it might help:

public bool HasItems
 
 getreturn LineItems.AsQueryable().Any(x => false);
 

share|improve this answer

answered Mar 8 at 5:29

neelesh bodgalneelesh bodgal

313

add a comment | 

Try this it might help:

public bool HasItems
 
 getreturn LineItems.AsQueryable().Any(x => false);
 

share|improve this answer

answered Mar 8 at 5:29

neelesh bodgalneelesh bodgal

313

public bool HasItems
 
 getreturn LineItems.AsQueryable().Any(x => false);
 

share|improve this answer

answered Mar 8 at 5:29

neelesh bodgalneelesh bodgal

313

answered Mar 8 at 5:29

neelesh bodgalneelesh bodgal

313

answered Mar 8 at 5:29

neelesh bodgalneelesh bodgal

313