ADO.Net Entity Save

Question

Hello I'm new to 3.5 framework. I'm developing one web based application in asp.3.5. There am using ADO.Net Entity framework for save and update. In my database there is lot table with relationship (Foreign key). My problem is how can we save foreign key field(parent table) value in child table. Because in child table object that key field not displaying. But i want save parent key field value in child table...Please help me. Thanks Aani

peter cho · Answer

Hi Aani Aani Did you get this resolve?

Amit Choudhary · Answer

hi friend i think there is some problem over there i opened your code and when wrote some lines for code it show the foreign key id for below line means for Add after pressing . PatAddId was there. Add.PatAddId i don't think any problem with it.

Aani Aani · Answer

Hello amith Thanks amith...But that is what my problem. Add.PatAddID = patid; Above line is problem line. That Add object does not contain definition for PatAddID (i.e) usually when press .(dot) after object it shows all the fields in our table but here that foreign key field only not showing. Not only for this table all the table in my db...Hope you understand my problem.

Amit Choudhary · Answer

i have modified some code your information was enough but i was not able to run the program. but get some hint for solution try the code below Tbl_Pateint pateint = new Tbl_Pateint(); pateint.PatName = TextBox1.Text; sample.AddToTbl_Pateint(pateint); sample.SaveChanges(); //after save this table i will get this primary key id. int patid = pateint.PatID; //This is child table info here pat id is Foreign key. // Now i need to save patient id into this child table Tbl_PatAddress Add = new Tbl_PatAddress(); Add.Address = TextBox2.Text; Add.City = TextBox3.Text; Add.State = TextBox4.Text; Add.Zip = TextBox5.Text; Add.PatAddID = patid; sample.SaveChanges(); i have marked red the newly added/Changed code lines. hope it helps you.

Aani Aani · Answer

Hello Sam Hobbs Thank you for replaying me....I know this SQL statements...But i want to do with ADO.Net entity framework.

Sam Hobbs · Answer

I am not familiar with the Entity framework but the following code should work for SQL Server. First add a select after the insert to get the Id; something similar to the following. Note that SCOPE_IDENTITY() is a sp. INSERT INTO Table1 (WhenDone) VALUES (@When); SELECT Id FROM Table1 WHERE (Id = SCOPE_IDENTITY()) The result of executing that should produce a one-record result that has one field; the identity from the previous insert.

Sam Hobbs · Answer

Amit: I think the owners of this web site want us to get all code posted instead of exchanged by email. In other words I think they want us to request that code from the person requesting assistance be posted so that everyone has a chance to help. Aani has done that; that is posted the code here. I think that you Amit have asked theLizard to post code from him so I am sure you understand what I mean. It's not a big thing but I hope it helps to mention this.

Aani Aani · Answer

Hi Amit Sorry for late reply...I have attached one small proj...Datebase backup in app_data folder...so u just create one like sample and restore that and change the web.config info....

Aani Aani · Answer

Hi Ya just wait....mine is big project so i will sent small one but same scenario .....

Amit Choudhary · Answer

hi friend send me your project i understand what you want but i think there is some other problem. I can help you.

Aani Aani · Answer

Hi Your explanation about foreign key relationship to child is correct. But my problem is not that. Here i want to save parent table key value to child tabel..Usually we need to create one object for child table and assign values into corresponding tables fields childtbl child=new childtbl(); child.id=1; child.name=Aani; child.FKId=2; but when i trying write above line (child.FKId=2). That FKId not showing in child object. This is what problem... How can i assign my parent table key into child table... hope you understand my problem... -- Regards Anandh Viswanathan.

Amit Choudhary · Answer

hi friend Well its not like that you are thinking the foreign key concept is based on check constraint. when you insert value in child it checks the value for its existence in parent table. This is what a foreign key constraint can do. you are asking about inserting automatically from parent to child. this issue is not related to parent child relation ship in foreign key constraint. you have to query on parent table based on some condition of child table. then use the parent PrimaryID to insert into child. you have to do it by writing code for it. its not automatic process hope you got my point.