DataTable foreign key

[Emre DÝNÇER]

Dear All,
is it possible to extract the DataColumn which is a foreign key of another
table.

foreach (DataRelation dr in dsIlce.Tables[0].ParentRelations) {

Console.WriteLine("123");

console.WriteLine(dr.ParentTable.TableName.ToString());

}

prints nothing unfortunately..



thanks in advance

emre dincer

 

[MrSmersh]

Try the sample you find here:
http://msdn2.microsoft.com/en-US/library/system.data.datatable.parentrelations.aspx

 

[Emre DÝNÇER]

actually i think i was unable to clarify my problem,
the situation is the dataTable belongs to a single table and the DataSet
class does not any
DataRelation object , what i am trying to do is to realize the foreign key
relationship at runtime.
that is i can not utilize DataRelation property.
i think i need another option to realize that a column represents a foreign
key
thanks in advance.
emre dincer

Try the sample you find here:
http://msdn2.microsoft.com/en-US/library/system.data.datatable.parentrelations.aspx

Dear All,
is it possible to extract the DataColumn which is a foreign key of
another
table.

foreach (DataRelation dr in dsIlce.Tables[0].ParentRelations) {

Console.WriteLine("123");

console.WriteLine(dr.ParentTable.TableName.ToString());

}

prints nothing unfortunately..



thanks in advance

emre dincer

 

[MrSmersh]

I'm afraid that I do not understand now...
Could you please explain again what you are trying to do?

actually i think i was unable to clarify my problem,
the situation is the dataTable belongs to a single table and the DataSet
class does not any
DataRelation object , what i am trying to do is to realize the foreign key
relationship at runtime.
that is i can not utilize DataRelation property.
i think i need another option to realize that a column represents a foreign
key
thanks in advance.
emre dincer

Try the sample you find here:
http://msdn2.microsoft.com/en-US/library/system.data.datatable.parentrelations.aspx

Dear All,
is it possible to extract the DataColumn which is a foreign key of
another
table.

foreach (DataRelation dr in dsIlce.Tables[0].ParentRelations) {

Console.WriteLine("123");

console.WriteLine(dr.ParentTable.TableName.ToString());

}

prints nothing unfortunately..



thanks in advance

emre dincer

 

[Emre DÝNÇER]

Thanks for your interest.
What i am trying to say is I dont declare any DataRelation object at design
time
and at runtime i have the instance of the DataSet , with these at hand , i
want to catch if one of the columns of datatable of the dataset is a foreign
key of another table.
DSCities dc=new DSCities(); //the dataset for the CitiesTable

I'm afraid that I do not understand now...
Could you please explain again what you are trying to do?

foreach (DataColumn dc in dc.Tables[0]) {
//want to realize if the column is a FK...
}
best regards
emre

actually i think i was unable to clarify my problem,
the situation is the dataTable belongs to a single table and the DataSet
class does not any
DataRelation object , what i am trying to do is to realize the foreign
key
relationship at runtime.
that is i can not utilize DataRelation property.
i think i need another option to realize that a column represents a
foreign
key
thanks in advance.
emre dincer

Try the sample you find here:
http://msdn2.microsoft.com/en-US/library/system.data.datatable.parentrelations.aspx

:

Dear All,
is it possible to extract the DataColumn which is a foreign key of
another
table.

foreach (DataRelation dr in dsIlce.Tables[0].ParentRelations) {

Console.WriteLine("123");

console.WriteLine(dr.ParentTable.TableName.ToString());

}

prints nothing unfortunately..



thanks in advance

emre dincer

 

[MrSmersh]

OK, I now understand even less.
How do you “fill†the dataset?
If the database used is SQL Server ADO.Net is able to give you catalog
information’s, hence a dataset with a corresponding structure, all this at
runtime. Otherwise what you put into the dataset you will have.

Thanks for your interest.
What i am trying to say is I dont declare any DataRelation object at design
time
and at runtime i have the instance of the DataSet , with these at hand , i
want to catch if one of the columns of datatable of the dataset is a foreign
key of another table.
DSCities dc=new DSCities(); //the dataset for the CitiesTable

I'm afraid that I do not understand now...
Could you please explain again what you are trying to do?

foreach (DataColumn dc in dc.Tables[0]) {
//want to realize if the column is a FK...
}
best regards
emre

actually i think i was unable to clarify my problem,
the situation is the dataTable belongs to a single table and the DataSet
class does not any
DataRelation object , what i am trying to do is to realize the foreign
key
relationship at runtime.
that is i can not utilize DataRelation property.
i think i need another option to realize that a column represents a
foreign
key
thanks in advance.
emre dincer
Try the sample you find here:
http://msdn2.microsoft.com/en-US/library/system.data.datatable.parentrelations.aspx

:

Dear All,
is it possible to extract the DataColumn which is a foreign key of
another
table.

foreach (DataRelation dr in dsIlce.Tables[0].ParentRelations) {

Console.WriteLine("123");

console.WriteLine(dr.ParentTable.TableName.ToString());

}

prints nothing unfortunately..



thanks in advance

emre dincer

 

[Emre DÝNÇER]

Hello Again,

i fill the ds in the following manner.





public DataSet VeriGetir(string ssql,string sTableName,bool bFillSchema)

{

OpenConnection();

SqlDataAdapter da = new SqlDataAdapter(ssql, mConnection);

try

{

DataSet ds = new DataSet();

if (mIsTransactional)

da.SelectCommand.Transaction = mTransaction;

if (bFillSchema)

da.FillSchema(ds, SchemaType.Source, sTableName);

da.Fill(ds, sTableName);

return ds;

}

catch (Exception ex)

{

HataLogla(ex,ssql);

throw (ex);

}

finally

{

CloseConnection();

}

}

OK, I now understand even less.
How do you "fill" the dataset?
If the database used is SQL Server ADO.Net is able to give you catalog
information's, hence a dataset with a corresponding structure, all this at
runtime. Otherwise what you put into the dataset you will have.

Thanks for your interest.
What i am trying to say is I dont declare any DataRelation object at
design
time
and at runtime i have the instance of the DataSet , with these at hand ,
i
want to catch if one of the columns of datatable of the dataset is a
foreign
key of another table.
DSCities dc=new DSCities(); //the dataset for the CitiesTable

I'm afraid that I do not understand now...
Could you please explain again what you are trying to do?

foreach (DataColumn dc in dc.Tables[0]) {
//want to realize if the column is a FK...
}
best regards
emre

:

actually i think i was unable to clarify my problem,
the situation is the dataTable belongs to a single table and the
DataSet
class does not any
DataRelation object , what i am trying to do is to realize the foreign
key
relationship at runtime.
that is i can not utilize DataRelation property.
i think i need another option to realize that a column represents a
foreign
key
thanks in advance.
emre dincer
Try the sample you find here:
http://msdn2.microsoft.com/en-US/library/system.data.datatable.parentrelations.aspx

:

Dear All,
is it possible to extract the DataColumn which is a foreign key of
another
table.

foreach (DataRelation dr in dsIlce.Tables[0].ParentRelations) {

Console.WriteLine("123");

console.WriteLine(dr.ParentTable.TableName.ToString());

}

prints nothing unfortunately..



thanks in advance

emre dincer

 

[MrSmersh]

OK I must recognize that I said something stupid, ADO.Net does not fill the
relations info.
Mea culpa X3.
You have 2 workarounds use OleDBConnection as shown here OleDBConnection
http://weblogs.asp.net/rosherove/archive/2003/06/29/9542.aspx or fill the
dataset as now and add the missing relations using the catalog stored
procedure (for SQL Server other databases uses catalog tables) sp_fkeys.

Hello Again,

i fill the ds in the following manner.





public DataSet VeriGetir(string ssql,string sTableName,bool bFillSchema)

{

OpenConnection();

SqlDataAdapter da = new SqlDataAdapter(ssql, mConnection);

try

{

DataSet ds = new DataSet();

if (mIsTransactional)

da.SelectCommand.Transaction = mTransaction;

if (bFillSchema)

da.FillSchema(ds, SchemaType.Source, sTableName);

da.Fill(ds, sTableName);

return ds;

}

catch (Exception ex)

{

HataLogla(ex,ssql);

throw (ex);

}

finally

{

CloseConnection();

}

}

OK, I now understand even less.
How do you "fill" the dataset?
If the database used is SQL Server ADO.Net is able to give you catalog
information's, hence a dataset with a corresponding structure, all this at
runtime. Otherwise what you put into the dataset you will have.

Thanks for your interest.
What i am trying to say is I dont declare any DataRelation object at
design
time
and at runtime i have the instance of the DataSet , with these at hand ,
i
want to catch if one of the columns of datatable of the dataset is a
foreign
key of another table.
DSCities dc=new DSCities(); //the dataset for the CitiesTable




I'm afraid that I do not understand now...
Could you please explain again what you are trying to do?
foreach (DataColumn dc in dc.Tables[0]) {
//want to realize if the column is a FK...
}
best regards
emre

:

actually i think i was unable to clarify my problem,
the situation is the dataTable belongs to a single table and the
DataSet
class does not any
DataRelation object , what i am trying to do is to realize the foreign
key
relationship at runtime.
that is i can not utilize DataRelation property.
i think i need another option to realize that a column represents a
foreign
key
thanks in advance.
emre dincer
Try the sample you find here:
http://msdn2.microsoft.com/en-US/library/system.data.datatable.parentrelations.aspx

:

Dear All,
is it possible to extract the DataColumn which is a foreign key of
another
table.

foreach (DataRelation dr in dsIlce.Tables[0].ParentRelations) {

Console.WriteLine("123");

console.WriteLine(dr.ParentTable.TableName.ToString());

}

prints nothing unfortunately..



thanks in advance

emre dincer