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cannot update value - LINQ

Posted on 2009-04-07
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Last Modified: 2013-11-11
I want update a property in a table (i' am using MS SQL server database) , but it get this error
" THIS PROPERTY IS READONLY"

how do i fix this?

also when I declare  a new linq database instance,
Dim Db As New SageEMSArchiveDataContext
I only get 4 overidable properties (normally this is 5)

I have
import  system.linq

I have checked my references, also stangely another project(on my system) does not have this issue.

any idea why this happens?




Dim Db As New SageEMSArchiveDataContext("Data Source=ADELN250;Initial Catalog=SageEMS;Integrated Security=True")
 
        Dim tbFile = (From files In Db.tbFiles _
                   Select files.Filename, files.ArchiveLocation Where Filename = fName).ToList(0)
 
        If Not tbFile Is Nothing Then
            tbFile.ArchiveLocation = "asdf" 'AT THIS POINT I GET AN ERROR SAYING THAT THIS PROPERTY IS READONLY
        End If

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Question by:manivineet
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4 Comments
 
LVL 9

Expert Comment

by:Sreedhar Vengala
ID: 24092909
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Author Comment

by:manivineet
ID: 24093037
no that didn't help at all
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Accepted Solution

by:
naspinski earned 500 total points
ID: 24094121
It is because you aren't selecting the whole item, just a few fields.  If you select a few fields, it is just for reading, as each entity does not have a key to tell the DB which one it is.  Just change

Dim tbFile = (From files In Db.tbFiles _
                   Select files.Filename, files.ArchiveLocation Where Filename = fName).ToList(0)

to
Dim tbFile = From files In Db.tbFiles _ files

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Author Comment

by:manivineet
ID: 24134262
well the problem was that my table didn't have primary key.
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