C# Linq to SQL:cannot add an entity that already exists

Question

I am using Linq for Insert,Delete and update the database in my code. While inserting data using InsertOnSubmit, I Am getting the cannot add an entity that already exists Exception. Please have a look my code

private static void AddNewPriceSettings(PRICE_SETTING priceSettingsInfo)
{
   PRICE_SETTING priceSetting = new PRICE_SETTING();
   priceSetting = priceSettingsInfo;           
   DataContext.CommonUsers.PRICE_SETTINGs.InsertOnSubmit(priceSettingsInfo);          
   DataContext.CommonUsers.SubmitChanges();
}

Kathiravan · Accepted Answer · 2012-07-26 13:30:10Z

2

just set the properties for the new priceSetting.

private static void AddNewPriceSettings(PRICE_SETTING priceSettingsInfo)
{
   PRICE_SETTING priceSetting = new PRICE_SETTING();
   //
   priceSetting.Prop1 = priceSettingsInfo.Prop1;
   priceSetting.Prop2 = priceSettingsInfo.Prop2;
   priceSetting.Prop3 = priceSettingsInfo.Prop3;
   // ...
   DataContext.CommonUsers.PRICE_SETTINGs.InsertOnSubmit(priceSetting );          
   DataContext.CommonUsers.SubmitChanges();
}

edited Jul 26, 2012 at 13:30

Kathiravan

551 silver badge7 bronze badges

answered Jul 26, 2012 at 12:50

user900202

Sign up to request clarification or add additional context in comments.

2 Comments

user900202 Over a year ago

by the way, you should use InsertOnSubmit(priceSetting); instead of InsertOnSubmit(priceSettingsInfo);

Kathiravan Over a year ago

Yes and thank you very much. it is working after including primary keys value.

CodeCaster · Accepted Answer · 2012-07-26 12:42:00Z

0

If you call AddNewPriceSettings() using an existing PRICE_SETTING object, you're indeed trying to add it again. The second line in your method does that. The new PRICE_SETTING(); you create on the first line is then not referenced to anymore and will be GC'ed without trying to insert it.

If you want to create a copy, you'll have to clone the priceSettingsInfo into the priceSetting variable (you can use various techniques for that) prior to inserting and submitting it.

answered Jul 26, 2012 at 12:42

CodeCaster

153k24 gold badges237 silver badges287 bronze badges

2 Comments

Kathiravan Over a year ago

Could you please tell me about clone?

CodeCaster Over a year ago

@user1063573 could you please show some effort? The easiest way perhaps is to create a copy constructor.

Anders Arpi · Accepted Answer · 2012-07-26 12:42:21Z

0

cannot add an entity that already exists

The problem is clearly stated by the error message. You already have a row in your database that contains the same entity as the one you are trying to insert.

How does SQL decide if two items are "the same"? It uses a key column, which usually is an integer id.

So that leads me to ask you - how does your column definitions look for the affected table? And where are you getting the PRICE_SETTING that is passed into the method?

The problem could also be that you are trying to perform an update on an already existing object - in that case you need to use different methods. Please share more info regarding the context.

answered Jul 26, 2012 at 12:42

Anders Arpi

8,4373 gold badges35 silver badges49 bronze badges

2 Comments

Kathiravan Over a year ago

I already deleted the previous data and i have filled new PRICE_SETTING data after deleting the old data.

Kathiravan Over a year ago

Instead of updating the data . I have deleted old data and tried to insert new data.

Collectives™ on Stack Overflow

C# Linq to SQL:cannot add an entity that already exists

3 Answers 3

2 Comments

2 Comments

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

2 Comments

2 Comments

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related