LINQ Issue - "Specified cast is not valid"

  • Thread starter Thread starter Paul Prewett
  • Start date Start date
P

Paul Prewett

I'm attempting to use LINQ to insert a record into a child table and I'm
receiving a "Specified cast is not valid" error that has something to do w/
the keys involved. The stack trace is:

======================
Message: Specified cast is not valid.

Type: System.InvalidCastException
Source: System.Data.Linq
TargetSite: Boolean TryCreateKeyFromValues(System.Object[], V ByRef)
HelpLink: null
Stack: at
System.Data.Linq.IdentityManager.StandardIdentityManager.SingleKeyManager`2.TryCreateKeyFromValues(Object[] values, V& v)
at
System.Data.Linq.IdentityManager.StandardIdentityManager.IdentityCache`2.Find(Object[] keyValues)
at System.Data.Linq.IdentityManager.StandardIdentityManager.Find(MetaType
type, Object[] keyValues)
at System.Data.Linq.CommonDataServices.GetCachedObject(MetaType type,
Object[] keyValues)
at System.Data.Linq.ChangeProcessor.GetOtherItem(MetaAssociation assoc,
Object instance)
at System.Data.Linq.ChangeProcessor.BuildEdgeMaps()
at System.Data.Linq.ChangeProcessor.SubmitChanges(ConflictMode failureMode)
at System.Data.Linq.DataContext.SubmitChanges(ConflictMode failureMode)
at System.Data.Linq.DataContext.SubmitChanges()

(.....)

======================

This error is being thrown on the following code:
============
ResponseDataContext db = new ResponseDataContext(m_ConnectionString);
CodebookVersion codebookVersion = db.CodebookVersions.Single(cv =>
cv.VersionTag == m_CodebookVersionTag);
ResponseCode rc = new ResponseCode()
{
SurveyQuestionName = "Q11",
Code = 3,
Description = "Yet another code"
};
codebookVersion.ResponseCodes.Add(rc);
db.SubmitChanges(); //exception gets thrown here
============

The tables in question have a FK relationship between the two of them.
The parent table's column is called 'id', is the PK, and is of type: INT
NOT NULL IDENTITY
The child table's column is called 'responseCodeTableId' and is of type: INT
NOT NULL

codebookVersion (parent class) maps to table tblResponseCodeTable
responseCode (childClass) maps to table tblResponseCode

If I execute SQL directly, it works. e.g.
INSERT INTO tblResponseCode
(responseCodeTableId, surveyQuestionName, code, description)
VALUES (13683, 'Q11', 3, 'Yet another code')


Updates to the same class work properly. e.g.
codebookVersion.ResponseCodes[0].Description = "BlahBlahBlah";
db.SubmitChanges(); //no exception - change is committed to db

I've examined the variable, rc, after the .Add() operation and it does,
indeed, receive the proper responseCodeTableId, just as I would expect since
I'm adding it to that collection.

tblResponseCodeTable's full definition:
COLUMN_NAME TYPE_NAME
id int identity
responseCodeTableId int
surveyQuestionName nvarchar
code smallint
description nvarchar
dtCreate smalldatetime

dtCreate has a default value of GetDate().


The only other bit of useful information that I can think of is that no SQL
is ever tried against the database, so LINQ is blowing up before it ever
tries (hence the error not being a SqlException). I've profiled and verified
that no attempt is made to execute any statements on the database.


Can anyone shed any light on this situation for me? What incredibly obvious
thing am I missing here?
 
Hi Paul,

From the issue description, I understand you're encounering some exception
when try inserting a main table record via a foreignkey associated table,
correct?

As you said that the direct T-SQL inserting approach work, have you tried
using the DataContext.Log to output the LINQ translated T-SQL code to see
whehter it matches the working SQL code?

#DataContext.Log - Logging LINQ To SQL Output to Console or Debugger Output
Window
http://www.davidhayden.com/blog/dave/archive/2007/08/17/DataContextLogLoggin
gLINQToSQLOutputConsoleDebuggerOuputWindow.aspx

Also, if possible, you can provide a simlified version of the two tables
and code(the DDL or table schema). I'd like to perform some tests on my
side.

Sincerely,

Steven Cheng

Microsoft MSDN Online Support Lead


Delighting our customers is our #1 priority. We welcome your comments and
suggestions about how we can improve the support we provide to you. Please
feel free to let my manager know what you think of the level of service
provided. You can send feedback directly to my manager at:
(e-mail address removed).

==================================================
Get notification to my posts through email? Please refer to
http://msdn.microsoft.com/en-us/subscriptions/aa948868.aspx#notifications.

Note: The MSDN Managed Newsgroup support offering is for non-urgent issues
where an initial response from the community or a Microsoft Support
Engineer within 1 business day is acceptable. Please note that each follow
up response may take approximately 2 business days as the support
professional working with you may need further investigation to reach the
most efficient resolution. The offering is not appropriate for situations
that require urgent, real-time or phone-based interactions or complex
project analysis and dump analysis issues. Issues of this nature are best
handled working with a dedicated Microsoft Support Engineer by contacting
Microsoft Customer Support Services (CSS) at
http://support.microsoft.com/select/default.aspx?target=assistance&ln=en-us.
==================================================
This posting is provided "AS IS" with no warranties, and confers no rights.

--------------------
From: =?Utf-8?B?UGF1bCBQcmV3ZXR0?= <[email protected]>
Subject: LINQ Issue - "Specified cast is not valid"
Date: Sat, 25 Oct 2008 17:41:01 -0700
Click to expand...
I'm attempting to use LINQ to insert a record into a child table and I'm
receiving a "Specified cast is not valid" error that has something to do w/
the keys involved. The stack trace is:

======================
Message: Specified cast is not valid.

Type: System.InvalidCastException
Source: System.Data.Linq
TargetSite: Boolean TryCreateKeyFromValues(System.Object[], V ByRef)
HelpLink: null
Stack: at
Click to expand...
System.Data.Linq.IdentityManager.StandardIdentityManager.SingleKeyManager`2.
TryCreateKeyFromValues(Object[] values, V& v)
at
Click to expand...
System.Data.Linq.IdentityManager.StandardIdentityManager.IdentityCache`2.Fin
d(Object[] keyValues)
at System.Data.Linq.IdentityManager.StandardIdentityManager.Find(MetaType
type, Object[] keyValues)
at System.Data.Linq.CommonDataServices.GetCachedObject(MetaType type,
Object[] keyValues)
at System.Data.Linq.ChangeProcessor.GetOtherItem(MetaAssociation assoc,
Object instance)
at System.Data.Linq.ChangeProcessor.BuildEdgeMaps()
at System.Data.Linq.ChangeProcessor.SubmitChanges(ConflictMode failureMode)
at System.Data.Linq.DataContext.SubmitChanges(ConflictMode failureMode)
at System.Data.Linq.DataContext.SubmitChanges()

(.....)

======================

This error is being thrown on the following code:
============
ResponseDataContext db = new ResponseDataContext(m_ConnectionString);
CodebookVersion codebookVersion = db.CodebookVersions.Single(cv =>
cv.VersionTag == m_CodebookVersionTag);
ResponseCode rc = new ResponseCode()
{
SurveyQuestionName = "Q11",
Code = 3,
Description = "Yet another code"
};
codebookVersion.ResponseCodes.Add(rc);
db.SubmitChanges(); //exception gets thrown here
============

The tables in question have a FK relationship between the two of them.
The parent table's column is called 'id', is the PK, and is of type: INT
NOT NULL IDENTITY
The child table's column is called 'responseCodeTableId' and is of type: INT
NOT NULL

codebookVersion (parent class) maps to table tblResponseCodeTable
responseCode (childClass) maps to table tblResponseCode

If I execute SQL directly, it works. e.g.
INSERT INTO tblResponseCode
(responseCodeTableId, surveyQuestionName, code, description)
VALUES (13683, 'Q11', 3, 'Yet another code')


Updates to the same class work properly. e.g.
codebookVersion.ResponseCodes[0].Description = "BlahBlahBlah";
db.SubmitChanges(); //no exception - change is committed to db

I've examined the variable, rc, after the .Add() operation and it does,
indeed, receive the proper responseCodeTableId, just as I would expect since
I'm adding it to that collection.

tblResponseCodeTable's full definition:
COLUMN_NAME TYPE_NAME
id int identity
responseCodeTableId int
surveyQuestionName nvarchar
code smallint
description nvarchar
dtCreate smalldatetime

dtC
Click to expand...
 
Hi Steven -

Thanks for taking a look at this.

The first table schema is listed in my original post.

tblResponseTable definition (which maps to CodebookVersion)
COLUMN_NAME TYPE_NAME
id int identity
versionTag nvarchar
responseVersionTag nvarchar
dtCreate smalldatetime

dtCreate again has a default value of GETDATE()

As for the generated T-SQL, as I see the issue, there is never any generated
T-SQL. The error is coming from LINQ before it generates the T-SQL. Would
using the DataContext Log still be instructive?


--
-Paul Prewett


"Steven Cheng" said:
Hi Paul,

From the issue description, I understand you're encounering some exception
when try inserting a main table record via a foreignkey associated table,
correct?

As you said that the direct T-SQL inserting approach work, have you tried
using the DataContext.Log to output the LINQ translated T-SQL code to see
whehter it matches the working SQL code?

#DataContext.Log - Logging LINQ To SQL Output to Console or Debugger Output
Window
http://www.davidhayden.com/blog/dave/archive/2007/08/17/DataContextLogLoggin
gLINQToSQLOutputConsoleDebuggerOuputWindow.aspx

Also, if possible, you can provide a simlified version of the two tables
and code(the DDL or table schema). I'd like to perform some tests on my
side.

Sincerely,

Steven Cheng

Microsoft MSDN Online Support Lead


Delighting our customers is our #1 priority. We welcome your comments and
suggestions about how we can improve the support we provide to you. Please
feel free to let my manager know what you think of the level of service
provided. You can send feedback directly to my manager at:
(e-mail address removed).

==================================================
Get notification to my posts through email? Please refer to
http://msdn.microsoft.com/en-us/subscriptions/aa948868.aspx#notifications.

Note: The MSDN Managed Newsgroup support offering is for non-urgent issues
where an initial response from the community or a Microsoft Support
Engineer within 1 business day is acceptable. Please note that each follow
up response may take approximately 2 business days as the support
professional working with you may need further investigation to reach the
most efficient resolution. The offering is not appropriate for situations
that require urgent, real-time or phone-based interactions or complex
project analysis and dump analysis issues. Issues of this nature are best
handled working with a dedicated Microsoft Support Engineer by contacting
Microsoft Customer Support Services (CSS) at
http://support.microsoft.com/select/default.aspx?target=assistance&ln=en-us.
==================================================
This posting is provided "AS IS" with no warranties, and confers no rights.

--------------------
From: =?Utf-8?B?UGF1bCBQcmV3ZXR0?= <[email protected]>
Subject: LINQ Issue - "Specified cast is not valid"
Date: Sat, 25 Oct 2008 17:41:01 -0700
Click to expand...
I'm attempting to use LINQ to insert a record into a child table and I'm
receiving a "Specified cast is not valid" error that has something to do w/
the keys involved. The stack trace is:

======================
Message: Specified cast is not valid.

Type: System.InvalidCastException
Source: System.Data.Linq
TargetSite: Boolean TryCreateKeyFromValues(System.Object[], V ByRef)
HelpLink: null
Stack: at
Click to expand...
System.Data.Linq.IdentityManager.StandardIdentityManager.SingleKeyManager`2.
TryCreateKeyFromValues(Object[] values, V& v)
at
Click to expand...
System.Data.Linq.IdentityManager.StandardIdentityManager.IdentityCache`2.Fin
d(Object[] keyValues)
at System.Data.Linq.IdentityManager.StandardIdentityManager.Find(MetaType
type, Object[] keyValues)
at System.Data.Linq.CommonDataServices.GetCachedObject(MetaType type,
Object[] keyValues)
at System.Data.Linq.ChangeProcessor.GetOtherItem(MetaAssociation assoc,
Object instance)
at System.Data.Linq.ChangeProcessor.BuildEdgeMaps()
at System.Data.Linq.ChangeProcessor.SubmitChanges(ConflictMode failureMode)
at System.Data.Linq.DataContext.SubmitChanges(ConflictMode failureMode)
at System.Data.Linq.DataContext.SubmitChanges()

(.....)

======================

This error is being thrown on the following code:
============
ResponseDataContext db = new ResponseDataContext(m_ConnectionString);
CodebookVersion codebookVersion = db.CodebookVersions.Single(cv =>
cv.VersionTag == m_CodebookVersionTag);
ResponseCode rc = new ResponseCode()
{
SurveyQuestionName = "Q11",
Code = 3,
Description = "Yet another code"
};
codebookVersion.ResponseCodes.Add(rc);
db.SubmitChanges(); //exception gets thrown here
============

The tables in question have a FK relationship between the two of them.
The parent table's column is called 'id', is the PK, and is of type: INT
NOT NULL IDENTITY
The child table's column is called 'responseCodeTableId' and is of type: INT
NOT NULL

codebookVersion (parent class) maps to table tblResponseCodeTable
responseCode (childClass) maps to table tblResponseCode

If I execute SQL directly, it works. e.g.
INSERT INTO tblResponseCode
(responseCodeTableId, surveyQuestionName, code, description)
VALUES (13683, 'Q11', 3, 'Yet another code')


Updates to the same class work properly. e.g.
codebookVersion.ResponseCodes[0].Description = "BlahBlahBlah";
db.SubmitChanges(); //no exception - change is committed to db

I've examined the variable, rc, after the .Add() operation and it does,
indeed, receive the proper responseCodeTableId, just as I would expect since
I'm adding it to that collection.

tblResponseCodeTable's full definition:
COLUMN_NAME TYPE_NAME
id int identity
responseCodeTableId int
surveyQuestionName nvarchar
code smallint
description nvarchar
dtCreate smalldatetime

dtC
Click to expand...
Click to expand...
 
Hi Paul,

Thanks for your reply.

Yes, if the error occurs before the LINQ has generated the T-SQL, the LOG
does be of less assistance.

I have just created two tables per your schema and performed some tests. It
seems my local program can sucessfully run the code snippet below:

====================
using (ResponseDataContextDataContext ctx = new
ResponseDataContextDataContext())
{

CodebookVersion codebookVersion =
ctx.CodebookVersions.Single(
cv =>
cv.id == 2);

MessageBox.Show(codebookVersion.ToString());

ResponseCode rc = new ResponseCode()
{
surveyQuestionName= "Q11",
code = 3,
description = "Yet another code"
};
codebookVersion.ResponseCodes.Add(rc);
ctx.SubmitChanges();
================

# for the two tables, I've manually added the foreign key constraint betwee
them. Not sure whether thsi matters.

And here is the LINQ log trace I've printed on my side:

=================
SELECT [t0].[id], [t0].[versionTag], [t0].[responseVersionTag],
[t0].[dtCreate]
FROM [dbo].[tblResponseTable] AS [t0]
WHERE [t0].[id] = @p0
-- @p0: Input Int (Size = 0; Prec = 0; Scale = 0) [2]
-- Context: SqlProvider(Sql2005) Model: AttributedMetaModel Build:
3.5.21022.8

INSERT INTO [dbo].[tblResponseCodeTable]([responseCodeTableId],
[surveyQuestionName],
Code: 
, [description], [dtCreate])
VALUES (@p0, @p1, @p2, @p3, @p4)

SELECT CONVERT(Int,SCOPE_IDENTITY()) AS [value]
-- @p0: Input Int (Size = 0; Prec = 0; Scale = 0) [2]
-- @p1: Input NVarChar (Size = 3; Prec = 0; Scale = 0) [Q11]
-- @p2: Input SmallInt (Size = 0; Prec = 0; Scale = 0) [3]
-- @p3: Input NVarChar (Size = 16; Prec = 0; Scale = 0) [Yet another code]
-- @p4: Input SmallDateTime (Size = 0; Prec = 0; Scale = 0) [Null]
-- Context: SqlProvider(Sql2005) Model: AttributedMetaModel Build:
3.5.21022.8
==================

If necessary, I can send you my test project for reference.

Sincerely,

Steven Cheng

Microsoft MSDN Online Support Lead


Delighting our customers is our #1 priority. We welcome your comments and
suggestions about how we

can improve the support we provide to you. Please feel free to let my
manager know what you think of

the level of service provided. You can send feedback directly to my manager
at: [email protected].


--------------------[QUOTE]
From: =?Utf-8?B?UGF1bCBQcmV3ZXR0?= <[email protected]>
References:  <[email protected]>[/QUOTE]
 
Hi Paul,

How are you doing? Have you got any progress on this or still need any
further help? As mentioned in my last thread, if you need my test project,
please feel free to contact me at the following address:

"Stcheng" + @ + "Microsoft.com"

Sincerely,

Steven Cheng

Microsoft MSDN Online Support Lead


Delighting our customers is our #1 priority. We welcome your comments and
suggestions about how we

can improve the support we provide to you. Please feel free to let my
manager know what you think of

the level of service provided. You can send feedback directly to my manager
at: (e-mail address removed).
 
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