Unusual behavior of Entity Framework - c#

I have the following code in C#:
public int AddSynonymBL(String[] syns, String word, User user)
{
int dismissedCounter = 0;
foreach (var item in syns)
{
BusinessLayerStatus.StatusBL res = this.dataAccess.AddSynonymDA(item.Trim().ToLowerInvariant(), word.Trim().ToLowerInvariant(), user);
if (res == BusinessLayerStatus.StatusBL.SynonymNotAdded)
++dismissedCounter;
}
int numberOfFailures = dismissedCounter;
return numberOfFailures;
}
And the following code is for AddSynonymDA method:
internal BusinessLayerStatus.StatusBL AddSynonymDA(string synonym, string word, User user)
{
try
{
Synonym newSyn = new Synonym()
{
Meaning = synonym
};
//The following if means that the searched word does not exist int the Searched table
if (this.context.Users.Where(a => a.Mail.Equals(user.Mail)).FirstOrDefault().Searcheds.Where(b => b.RealWord.Equals(word)).Count() == validNumberForKeyValues)
{
this.context.Users.Where(a => a.Mail.Equals(user.Mail)).FirstOrDefault().Searcheds.Where(b => b.RealWord.Equals(word)).FirstOrDefault().Synonyms.Add(newSyn);
this.context.SaveChanges();
return BusinessLayerStatus.StatusBL.SynonymAdded;
}
else
return BusinessLayerStatus.StatusBL.SynonymNotAdded;
}
catch (Exception ex)
{
ExceptionAction(ex);
return BusinessLayerStatus.StatusBL.SynonymNotAdded;
}
}
I am using Entity Framework. I have a table which contains an Id, a word column. Both of them together have unique key constraint in the database. My main code is as follows:
public static void Main()
{
EngineEntities context = new EngineEntities();
BusinessLogic bl = new BusinessLogic();
String[] s = new String[] { "java", "DB" };
Console.WriteLine(bl.AddSynonymBL(s, "Java", new User() { Mail = "media" }));
}
When I add a value which does not exist in the table everything is fine but when I add a value which already exists in the table, calling this.context.SaveChanges(); in the AddSynonymDA method, always throws an exception which was for the previous first exception which caused the first exception and nothing is added to database even if they do not exist in the database. Why is that?
I get the following error which shows that Java already exists. The problem is that Java is for the first call, as the second call, I have passed DB not Java.
{"Violation of UNIQUE KEY constraint 'IX_Searched'. Cannot insert duplicate key in object 'dbo.Searched'. The duplicate key value is (java, 2).\r\nThe statement has been terminated."}

I suspect that you have not set a column to be an Identity column in your database
In other words when you are inserting an entity you need a column to be automatically incrementing.
The way I do this is for example using SQL server:
ALTER TABLE [User] DROP COLUMN [ID];
ALTER TABLE [User]
ADD [ID] integer identity not null;
If you do not have an ID column already you do not need the first line.
After this, update your EF model in your project by deleting the User table and right clicking and Updating Model from Database and select the table.
So now when you insert new entries in you EF model, the ID column will be automatically incremented and you won't get an error.

you must initially check whether the item exists or not, since you seem to have a unique constraint, then you should utilize the attributes of reference in your code .

Related

String or binary data would be truncated exception when inserting data [duplicate]

I am running data.bat file with the following lines:
Rem Tis batch file will populate tables
cd\program files\Microsoft SQL Server\MSSQL
osql -U sa -P Password -d MyBusiness -i c:\data.sql
The contents of the data.sql file is:
insert Customers
(CustomerID, CompanyName, Phone)
Values('101','Southwinds','19126602729')
There are 8 more similar lines for adding records.
When I run this with start > run > cmd > c:\data.bat, I get this error message:
1>2>3>4>5>....<1 row affected>
Msg 8152, Level 16, State 4, Server SP1001, Line 1
string or binary data would be truncated.
<1 row affected>
<1 row affected>
<1 row affected>
<1 row affected>
<1 row affected>
<1 row affected>
Also, I am a newbie obviously, but what do Level #, and state # mean, and how do I look up error messages such as the one above: 8152?
From #gmmastros's answer
Whenever you see the message....
string or binary data would be truncated
Think to yourself... The field is NOT big enough to hold my data.
Check the table structure for the customers table. I think you'll find that the length of one or more fields is NOT big enough to hold the data you are trying to insert. For example, if the Phone field is a varchar(8) field, and you try to put 11 characters in to it, you will get this error.
I had this issue although data length was shorter than the field length.
It turned out that the problem was having another log table (for audit trail), filled by a trigger on the main table, where the column size also had to be changed.
In one of the INSERT statements you are attempting to insert a too long string into a string (varchar or nvarchar) column.
If it's not obvious which INSERT is the offender by a mere look at the script, you could count the <1 row affected> lines that occur before the error message. The obtained number plus one gives you the statement number. In your case it seems to be the second INSERT that produces the error.
Just want to contribute with additional information: I had the same issue and it was because of the field wasn't big enough for the incoming data and this thread helped me to solve it (the top answer clarifies it all).
BUT it is very important to know what are the possible reasons that may cause it.
In my case i was creating the table with a field like this:
Select '' as Period, * From Transactions Into #NewTable
Therefore the field "Period" had a length of Zero and causing the Insert operations to fail. I changed it to "XXXXXX" that is the length of the incoming data and it now worked properly (because field now had a lentgh of 6).
I hope this help anyone with same issue :)
Some of your data cannot fit into your database column (small). It is not easy to find what is wrong. If you use C# and Linq2Sql, you can list the field which would be truncated:
First create helper class:
public class SqlTruncationExceptionWithDetails : ArgumentOutOfRangeException
{
public SqlTruncationExceptionWithDetails(System.Data.SqlClient.SqlException inner, DataContext context)
: base(inner.Message + " " + GetSqlTruncationExceptionWithDetailsString(context))
{
}
/// <summary>
/// PArt of code from following link
/// http://stackoverflow.com/questions/3666954/string-or-binary-data-would-be-truncated-linq-exception-cant-find-which-fiel
/// </summary>
/// <param name="context"></param>
/// <returns></returns>
static string GetSqlTruncationExceptionWithDetailsString(DataContext context)
{
StringBuilder sb = new StringBuilder();
foreach (object update in context.GetChangeSet().Updates)
{
FindLongStrings(update, sb);
}
foreach (object insert in context.GetChangeSet().Inserts)
{
FindLongStrings(insert, sb);
}
return sb.ToString();
}
public static void FindLongStrings(object testObject, StringBuilder sb)
{
foreach (var propInfo in testObject.GetType().GetProperties())
{
foreach (System.Data.Linq.Mapping.ColumnAttribute attribute in propInfo.GetCustomAttributes(typeof(System.Data.Linq.Mapping.ColumnAttribute), true))
{
if (attribute.DbType.ToLower().Contains("varchar"))
{
string dbType = attribute.DbType.ToLower();
int numberStartIndex = dbType.IndexOf("varchar(") + 8;
int numberEndIndex = dbType.IndexOf(")", numberStartIndex);
string lengthString = dbType.Substring(numberStartIndex, (numberEndIndex - numberStartIndex));
int maxLength = 0;
int.TryParse(lengthString, out maxLength);
string currentValue = (string)propInfo.GetValue(testObject, null);
if (!string.IsNullOrEmpty(currentValue) && maxLength != 0 && currentValue.Length > maxLength)
{
//string is too long
sb.AppendLine(testObject.GetType().Name + "." + propInfo.Name + " " + currentValue + " Max: " + maxLength);
}
}
}
}
}
}
Then prepare the wrapper for SubmitChanges:
public static class DataContextExtensions
{
public static void SubmitChangesWithDetailException(this DataContext dataContext)
{
//http://stackoverflow.com/questions/3666954/string-or-binary-data-would-be-truncated-linq-exception-cant-find-which-fiel
try
{
//this can failed on data truncation
dataContext.SubmitChanges();
}
catch (SqlException sqlException) //when (sqlException.Message == "String or binary data would be truncated.")
{
if (sqlException.Message == "String or binary data would be truncated.") //only for EN windows - if you are running different window language, invoke the sqlException.getMessage on thread with EN culture
throw new SqlTruncationExceptionWithDetails(sqlException, dataContext);
else
throw;
}
}
}
Prepare global exception handler and log truncation details:
protected void Application_Error(object sender, EventArgs e)
{
Exception ex = Server.GetLastError();
string message = ex.Message;
//TODO - log to file
}
Finally use the code:
Datamodel.SubmitChangesWithDetailException();
Another situation in which you can get this error is the following:
I had the same error and the reason was that in an INSERT statement that received data from an UNION, the order of the columns was different from the original table. If you change the order in #table3 to a, b, c, you will fix the error.
select a, b, c into #table1
from #table0
insert into #table1
select a, b, c from #table2
union
select a, c, b from #table3
on sql server you can use SET ANSI_WARNINGS OFF like this:
using (SqlConnection conn = new SqlConnection("Data Source=XRAYGOAT\\SQLEXPRESS;Initial Catalog='Healthy Care';Integrated Security=True"))
{
conn.Open();
using (var trans = conn.BeginTransaction())
{
try
{
using cmd = new SqlCommand("", conn, trans))
{
cmd.CommandText = "SET ANSI_WARNINGS OFF";
cmd.ExecuteNonQuery();
cmd.CommandText = "YOUR INSERT HERE";
cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
cmd.CommandText = "SET ANSI_WARNINGS ON";
cmd.ExecuteNonQuery();
trans.Commit();
}
}
catch (Exception)
{
trans.Rollback();
}
}
conn.Close();
}
I had the same issue. The length of my column was too short.
What you can do is either increase the length or shorten the text you want to put in the database.
Also had this problem occurring on the web application surface.
Eventually found out that the same error message comes from the SQL update statement in the specific table.
Finally then figured out that the column definition in the relating history table(s) did not map the original table column length of nvarchar types in some specific cases.
I had the same problem, even after increasing the size of the problematic columns in the table.
tl;dr: The length of the matching columns in corresponding Table Types may also need to be increased.
In my case, the error was coming from the Data Export service in Microsoft Dynamics CRM, which allows CRM data to be synced to an SQL Server DB or Azure SQL DB.
After a lengthy investigation, I concluded that the Data Export service must be using Table-Valued Parameters:
You can use table-valued parameters to send multiple rows of data to a Transact-SQL statement or a routine, such as a stored procedure or function, without creating a temporary table or many parameters.
As you can see in the documentation above, Table Types are used to create the data ingestion procedure:
CREATE TYPE LocationTableType AS TABLE (...);
CREATE PROCEDURE dbo.usp_InsertProductionLocation
#TVP LocationTableType READONLY
Unfortunately, there is no way to alter a Table Type, so it has to be dropped & recreated entirely. Since my table has over 300 fields (😱), I created a query to facilitate the creation of the corresponding Table Type based on the table's columns definition (just replace [table_name] with your table's name):
SELECT 'CREATE TYPE [table_name]Type AS TABLE (' + STRING_AGG(CAST(field AS VARCHAR(max)), ',' + CHAR(10)) + ');' AS create_type
FROM (
SELECT TOP 5000 COLUMN_NAME + ' ' + DATA_TYPE
+ IIF(CHARACTER_MAXIMUM_LENGTH IS NULL, '', CONCAT('(', IIF(CHARACTER_MAXIMUM_LENGTH = -1, 'max', CONCAT(CHARACTER_MAXIMUM_LENGTH,'')), ')'))
+ IIF(DATA_TYPE = 'decimal', CONCAT('(', NUMERIC_PRECISION, ',', NUMERIC_SCALE, ')'), '')
AS field
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = '[table_name]'
ORDER BY ORDINAL_POSITION) AS T;
After updating the Table Type, the Data Export service started functioning properly once again! :)
When I tried to execute my stored procedure I had the same problem because the size of the column that I need to add some data is shorter than the data I want to add.
You can increase the size of the column data type or reduce the length of your data.
A 2016/2017 update will show you the bad value and column.
A new trace flag will swap the old error for a new 2628 error and will print out the column and offending value. Traceflag 460 is available in the latest cumulative update for 2016 and 2017:
https://support.microsoft.com/en-sg/help/4468101/optional-replacement-for-string-or-binary-data-would-be-truncated
Just make sure that after you've installed the CU that you enable the trace flag, either globally/permanently on the server:
...or with DBCC TRACEON:
https://learn.microsoft.com/en-us/sql/t-sql/database-console-commands/dbcc-traceon-trace-flags-transact-sql?view=sql-server-ver15
Another situation, in which this error may occur is in
SQL Server Management Studio. If you have "text" or "ntext" fields in your table,
no matter what kind of field you are updating (for example bit or integer).
Seems that the Studio does not load entire "ntext" fields and also updates ALL fields instead of the modified one.
To solve the problem, exclude "text" or "ntext" fields from the query in Management Studio
This Error Comes only When any of your field length is greater than the field length specified in sql server database table structure.
To overcome this issue you have to reduce the length of the field Value .
Or to increase the length of database table field .
If someone is encountering this error in a C# application, I have created a simple way of finding offending fields by:
Getting the column width of all the columns of a table where we're trying to make this insert/ update. (I'm getting this info directly from the database.)
Comparing the column widths to the width of the values we're trying to insert/ update.
Assumptions/ Limitations:
The column names of the table in the database match with the C# entity fields. For eg: If you have a column like this in database:
You need to have your Entity with the same column name:
public class SomeTable
{
// Other fields
public string SourceData { get; set; }
}
You're inserting/ updating 1 entity at a time. It'll be clearer in the demo code below. (If you're doing bulk inserts/ updates, you might want to either modify it or use some other solution.)
Step 1:
Get the column width of all the columns directly from the database:
// For this, I took help from Microsoft docs website:
// https://learn.microsoft.com/en-us/dotnet/api/system.data.sqlclient.sqlconnection.getschema?view=netframework-4.7.2#System_Data_SqlClient_SqlConnection_GetSchema_System_String_System_String___
private static Dictionary<string, int> GetColumnSizesOfTableFromDatabase(string tableName, string connectionString)
{
var columnSizes = new Dictionary<string, int>();
using (var connection = new SqlConnection(connectionString))
{
// Connect to the database then retrieve the schema information.
connection.Open();
// You can specify the Catalog, Schema, Table Name, Column Name to get the specified column(s).
// You can use four restrictions for Column, so you should create a 4 members array.
String[] columnRestrictions = new String[4];
// For the array, 0-member represents Catalog; 1-member represents Schema;
// 2-member represents Table Name; 3-member represents Column Name.
// Now we specify the Table_Name and Column_Name of the columns what we want to get schema information.
columnRestrictions[2] = tableName;
DataTable allColumnsSchemaTable = connection.GetSchema("Columns", columnRestrictions);
foreach (DataRow row in allColumnsSchemaTable.Rows)
{
var columnName = row.Field<string>("COLUMN_NAME");
//var dataType = row.Field<string>("DATA_TYPE");
var characterMaxLength = row.Field<int?>("CHARACTER_MAXIMUM_LENGTH");
// I'm only capturing columns whose Datatype is "varchar" or "char", i.e. their CHARACTER_MAXIMUM_LENGTH won't be null.
if(characterMaxLength != null)
{
columnSizes.Add(columnName, characterMaxLength.Value);
}
}
connection.Close();
}
return columnSizes;
}
Step 2:
Compare the column widths with the width of the values we're trying to insert/ update:
public static Dictionary<string, string> FindLongBinaryOrStringFields<T>(T entity, string connectionString)
{
var tableName = typeof(T).Name;
Dictionary<string, string> longFields = new Dictionary<string, string>();
var objectProperties = GetProperties(entity);
//var fieldNames = objectProperties.Select(p => p.Name).ToList();
var actualDatabaseColumnSizes = GetColumnSizesOfTableFromDatabase(tableName, connectionString);
foreach (var dbColumn in actualDatabaseColumnSizes)
{
var maxLengthOfThisColumn = dbColumn.Value;
var currentValueOfThisField = objectProperties.Where(f => f.Name == dbColumn.Key).First()?.GetValue(entity, null)?.ToString();
if (!string.IsNullOrEmpty(currentValueOfThisField) && currentValueOfThisField.Length > maxLengthOfThisColumn)
{
longFields.Add(dbColumn.Key, $"'{dbColumn.Key}' column cannot take the value of '{currentValueOfThisField}' because the max length it can take is {maxLengthOfThisColumn}.");
}
}
return longFields;
}
public static List<PropertyInfo> GetProperties<T>(T entity)
{
//The DeclaredOnly flag makes sure you only get properties of the object, not from the classes it derives from.
var properties = entity.GetType()
.GetProperties(System.Reflection.BindingFlags.Public
| System.Reflection.BindingFlags.Instance
| System.Reflection.BindingFlags.DeclaredOnly)
.ToList();
return properties;
}
Demo:
Let's say we're trying to insert someTableEntity of SomeTable class that is modeled in our app like so:
public class SomeTable
{
[Key]
public long TicketID { get; set; }
public string SourceData { get; set; }
}
And it's inside our SomeDbContext like so:
public class SomeDbContext : DbContext
{
public DbSet<SomeTable> SomeTables { get; set; }
}
This table in Db has SourceData field as varchar(16) like so:
Now we'll try to insert value that is longer than 16 characters into this field and capture this information:
public void SaveSomeTableEntity()
{
var connectionString = "server=SERVER_NAME;database=DB_NAME;User ID=SOME_ID;Password=SOME_PASSWORD;Connection Timeout=200";
using (var context = new SomeDbContext(connectionString))
{
var someTableEntity = new SomeTable()
{
SourceData = "Blah-Blah-Blah-Blah-Blah-Blah"
};
context.SomeTables.Add(someTableEntity);
try
{
context.SaveChanges();
}
catch (Exception ex)
{
if (ex.GetBaseException().Message == "String or binary data would be truncated.\r\nThe statement has been terminated.")
{
var badFieldsReport = "";
List<string> badFields = new List<string>();
// YOU GOT YOUR FIELDS RIGHT HERE:
var longFields = FindLongBinaryOrStringFields(someTableEntity, connectionString);
foreach (var longField in longFields)
{
badFields.Add(longField.Key);
badFieldsReport += longField.Value + "\n";
}
}
else
throw;
}
}
}
The badFieldsReport will have this value:
'SourceData' column cannot take the value of
'Blah-Blah-Blah-Blah-Blah-Blah' because the max length it can take is
16.
Kevin Pope's comment under the accepted answer was what I needed.
The problem, in my case, was that I had triggers defined on my table that would insert update/insert transactions into an audit table, but the audit table had a data type mismatch where a column with VARCHAR(MAX) in the original table was stored as VARCHAR(1) in the audit table, so my triggers were failing when I would insert anything greater than VARCHAR(1) in the original table column and I would get this error message.
I used a different tactic, fields that are allocated 8K in some places. Here only about 50/100 are used.
declare #NVPN_list as table
nvpn varchar(50)
,nvpn_revision varchar(5)
,nvpn_iteration INT
,mpn_lifecycle varchar(30)
,mfr varchar(100)
,mpn varchar(50)
,mpn_revision varchar(5)
,mpn_iteration INT
-- ...
) INSERT INTO #NVPN_LIST
SELECT left(nvpn ,50) as nvpn
,left(nvpn_revision ,10) as nvpn_revision
,nvpn_iteration
,left(mpn_lifecycle ,30)
,left(mfr ,100)
,left(mpn ,50)
,left(mpn_revision ,5)
,mpn_iteration
,left(mfr_order_num ,50)
FROM [DASHBOARD].[dbo].[mpnAttributes] (NOLOCK) mpna
I wanted speed, since I have 1M total records, and load 28K of them.
This error may be due to less field size than your entered data.
For e.g. if you have data type nvarchar(7) and if your value is 'aaaaddddf' then error is shown as:
string or binary data would be truncated
You simply can't beat SQL Server on this.
You can insert into a new table like this:
select foo, bar
into tmp_new_table_to_dispose_later
from my_table
and compare the table definition with the real table you want to insert the data into.
Sometime it's helpful sometimes it's not.
If you try inserting in the final/real table from that temporary table it may just work (due to data conversion working differently than SSMS for example).
Another alternative is to insert the data in chunks, instead of inserting everything immediately you insert with top 1000 and you repeat the process, till you find a chunk with an error. At least you have better visibility on what's not fitting into the table.

Trying to Query a SQL Server from ASP.net MVC 4 using C#

I am trying to use a query to find the last ID (entry) in the table called ContributorUser in the database FPTContributorUsers and then add in a new entry thus assigning it the next available ID.
the below code allows me to add data to the table in the database however when I run it the ID (new entry to the table) shows as 0 and not 4. because I currently have three entries in my table
[HttpPost]
public ActionResult AddContributor(ContributorUsers AddCont)
{
if (AddCont.UserID == null)
{
throw new HttpException(404, "Please enter a valid RacfId");
}
else
{
FPTContributorUsers NewUser = new FPTContributorUsers();
NewUser.UserID = AddCont.UserID;
NewUser.ID = AddCont.ID;
db.ContributorUsers.Add(NewUser);
db.SaveChanges();
return RedirectToAction("index");
}
}
Have you thought about just making that the primary key and having it auto increment so you don't need to determine what it is yourself? That's usually the best way to go about handling actual ID's in my experience.
To do this in SQL Server follow these steps
To do this in MySQL follow these steps
As a note, if you do this you will need to update your EF model.
The other way to do it if you can't edit the database is to use MAX() for that column which will return the highest ID value, then just add one to it, no EF model updating required.
Try removing the "NewUser.ID = AddCont.ID" line and wait to get the NewUser.ID until after "db.SaveChanges()"
else
{
FPTContributorUsers NewUser = new FPTContributorUsers();
NewUser.UserID = AddCont.UserID;
db.ContributorUsers.Add(NewUser);
db.SaveChanges();
return RedirectToAction("index");
}
If the NewUser.ID property is an Identity Field in the database, it will not get populated until after the record is created during the SaveChanges() transaction commit.
Try Reload() the DB Context after SaveChanges() before you call the NewUser.ID so that the context is up-to-date

EF 5 Conditional Mapping

I'm using EF 5 Database first approach in my MVC application. all of my tables uses a Field called Deleted which is a boolean field to mark a record is deleted.
I'm trying to get rid of the requirement of having to check Deleted == false every time I query my database. The very straightforward way of doing this is to use a conditional mapping in the edmx file where EF always return data that are not deleted. That's all good.
But the problem of doing this condition mapping is that, when I want to allow the user to delete some record for e.g Address from their address book I don't have access to Delete field from EF as I used it in the conditional mapping and therefore I have to look for another option to allow user to delete a record.
The way I thought is to create a stored proc that handle the delete query and call it when I want to delete the record.
Is there a better way of doing this? Is it possible to make the Delete field accessible even it is used in the conditional mapping?
I have a working solution for Soft Delete in Entity Framework Code First that may help.
The key is that you add a discriminator to every model that you want to be able to soft delete. In code first that is done like this:
modelBuilder.Entity<Foo>().Map(m => m.Requires("IsDeleted").HasValue(false));
This makes it invisible to the context and therefore you have to do the deletes using sql.
If this is the equivalent of your "conditional mapping" in Database First then one way to modify the sql is to override SaveChanges and run sql from there:
public override int SaveChanges()
{
foreach (var entry in ChangeTracker.Entries()
.Where(p => p.State == EntityState.Deleted
&& p.Entity is ModelBase))//I do have a base class for entities with a single
//"ID" property - all my entities derive from this,
//but you could use ISoftDelete here
SoftDelete(entry);
return base.SaveChanges();
}
private void SoftDelete(DbEntityEntry entry)
{
var e = entry.Entity as ModelBase;
string tableName = GetTableName(e.GetType());
Database.ExecuteSqlCommand(
String.Format("UPDATE {0} SET IsDeleted = 1 WHERE ID = #id", tableName)
, new SqlParameter("id", e.ID));
//Marking it Unchanged prevents the hard delete
//entry.State = EntityState.Unchanged;
//So does setting it to Detached:
//And that is what EF does when it deletes an item
//http://msdn.microsoft.com/en-us/data/jj592676.aspx
entry.State = EntityState.Detached;
}
Method used to Get Table Name explained here
That is the way I used to do it. Probably irrelevant to your Database First approach in EF5, but I have now moved to doing it in stored procedures. EF6 Code First generates CreateStoredProcedure calls in Migration files. I replace these with this.CreateDeleteProcedure("dbo.Foo_Delete", "[dbo].[Foos]"); - which is a call to my own extension method:
public static class MigrationExtensions
{
internal static string DeleteSqlFormat
{
//I also hard delete anything deleted more than a day ago in the same table
get { return "DELETE FROM {0} WHERE IsDeleted = 1 AND DATEADD(DAY, 1, DeletedAt) < GETUTCDATE(); UPDATE {0} SET IsDeleted = 1, DeletedAt = GETUTCDATE() WHERE ID = #ID;"; }
}
internal static void CreateDeleteProcedure(this DbMigration migration, string procName, string tableName)
{
migration.CreateStoredProcedure(
procName,
p => new
{
ID = p.Int(),
},
body:
string.Format(MigrationExtensions.DeleteSqlFormat, tableName)
);
}
}

How to insert child object with one to one relationship in Linq to SQL

EDIT
Ok everything I was doing code wise was correct I had placed the relationship on the tables wrong!
Question
I have a one to one relationship from task to message. When inserting new items I am getting a foreign key violation.
Details:
DB Structure
Task
ID (Primary Key, Guid, Default = NEWID())
MessageID (Unique Index with foreign key pointing to Message.ID)
Message
ID (Primary Key, Guid, Default = NEWID())
The dbml settings for the primary keys on each table have Auto Generate Value set to true and Auto-Sync set to OnInsert
I have the following code to insert the new objects
var objMessage = new Data.Message()
{
Body = "",
Subject = ""
};
Context.Messages.InsertOnSubmit(objMessage);
var objTask = new Data.Task()
{
Message = objMessage
};
Context.Tasks.InsertOnSubmit(objTask);
Context.SubmitChanges();
This throws a SQL error foreign key constrain violated.
The SQL profiling shows linq to sql is inserting task before message which it can't do as it needs the id from message so of course this causes a foreign key violation.
Where am I going wrong in this?
The problem what I can see is the first InsertOnSubmit. If you want to add it to the related table then I do not think you need the first InsertOnSubmit. Because when you insert the main object the child object will also be inserted with it's foreign key.
I think you can just do it like this:
var objTask = new Data.Task()
{
Message = new Data.Message()
{
Body = "",
Subject = ""
}
};
Context.Tasks.InsertOnSubmit(objTask);
Context.SubmitChanges();
Try to do this :
var objMessage = new Data.Message()
{
Body = "",
Subject = ""
};
Context.Messages.InsertOnSubmit(objMessage);
Context.SubmitChanges();
var objTask = new Data.Task()
{
Message = objMessage
};
Context.Tasks.InsertOnSubmit(objTask);
Context.SubmitChanges();
You must SubmitChanges before using the new record

Self Tracking Entities not returning modified object

I have the following function to update and insert a record in the table
public DASInput UpdateDASInputTable(DASInput fileSetData, Guid programID)
{
string connectionString = GetConnectionString(programID);
BI_ProgramConfigurationEntities dataContext = new BI_ProgramConfigurationEntities(connectionString);
dataContext.DASInputs.ApplyChanges(fileSetData);
dataContext.SaveChanges(System.Data.Objects.SaveOptions.DetectChangesBeforeSave);
fileSetData = dataContext.DASInputs.FirstOrDefault();
return fileSetData;
}
When I make first call with a new object of type DASInput, then it gets inserted correctly in the database. (DASInput table has the primary key as int with identity specification on).
But this first time insertion does not return the modified value of the primary key of the DASInput table.
So on every subsequent call a new record gets inserted in the database. I want the primary key(self generated by DB) to be returned to the client when the record gets inserted.
Isn't the syntax for adding an entity into a linq controlled database more along the lines of :
context.Table.AddObject(newStore);
//or
context.Table.Add(newStore);
context.SaveChanges();
I do answer this tentatively, not being hugely knowledgeable on LINQ.

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