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DataTable foreign keyis 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 Try the sample you find here:
http://msdn2.microsoft.com/en-US/library/system.data.datatable.parentrelations.aspx Show quote "Emre DÃNÇER" wrote: > 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 > > > 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 Show quote "MrSmersh" <MrSme***@discussions.microsoft.com> wrote in message news:F83BF6D0-BFBF-4F72-9AC5-510F41236EA5@microsoft.com... > Try the sample you find here: > http://msdn2.microsoft.com/en-US/library/system.data.datatable.parentrelations.aspx > > "Emre DYNÇER" wrote: > >> 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 >> >> >> I'm afraid that I do not understand now...
Could you please explain again what you are trying to do? Show quote "Emre DÃNÇER" wrote: > 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 > "MrSmersh" <MrSme***@discussions.microsoft.com> wrote in message > news:F83BF6D0-BFBF-4F72-9AC5-510F41236EA5@microsoft.com... > > Try the sample you find here: > > http://msdn2.microsoft.com/en-US/library/system.data.datatable.parentrelations.aspx > > > > "Emre DYNÇER" wrote: > > > >> 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 > >> > >> > >> > > > 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 "MrSmersh" <MrSme***@discussions.microsoft.com> wrote in message foreach (DataColumn dc in dc.Tables[0]) {news:52B01D15-F793-4353-A32E-F624190134DA@microsoft.com... > I'm afraid that I do not understand now... > Could you please explain again what you are trying to do? //want to realize if the column is a FK... } best regards emre Show quote > > "Emre DYNÇER" wrote: > >> 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 >> "MrSmersh" <MrSme***@discussions.microsoft.com> wrote in message >> news:F83BF6D0-BFBF-4F72-9AC5-510F41236EA5@microsoft.com... >> > Try the sample you find here: >> > http://msdn2.microsoft.com/en-US/library/system.data.datatable.parentrelations.aspx >> > >> > "Emre DYNÇER" wrote: >> > >> >> 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 >> >> >> >> >> >> >> >> >> 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. Show quote "Emre DÃNÇER" wrote: > 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 > > > > > "MrSmersh" <MrSme***@discussions.microsoft.com> wrote in message > news:52B01D15-F793-4353-A32E-F624190134DA@microsoft.com... > > 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 > > > > "Emre DYNÇER" wrote: > > > >> 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 > >> "MrSmersh" <MrSme***@discussions.microsoft.com> wrote in message > >> news:F83BF6D0-BFBF-4F72-9AC5-510F41236EA5@microsoft.com... > >> > Try the sample you find here: > >> > http://msdn2.microsoft.com/en-US/library/system.data.datatable.parentrelations.aspx > >> > > >> > "Emre DYNÇER" wrote: > >> > > >> >> 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 > >> >> > >> >> > >> >> > >> > >> > >> > > > 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(); } } Show quote "MrSmersh" <MrSme***@discussions.microsoft.com> wrote in message news:B627E65E-E904-4A82-8065-DCADD2CF5425@microsoft.com... > 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. > > > "Emre DYNÇER" wrote: > >> 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 >> >> >> >> >> "MrSmersh" <MrSme***@discussions.microsoft.com> wrote in message >> news:52B01D15-F793-4353-A32E-F624190134DA@microsoft.com... >> > 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 >> > >> > "Emre DYNÇER" wrote: >> > >> >> 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 >> >> "MrSmersh" <MrSme***@discussions.microsoft.com> wrote in message >> >> news:F83BF6D0-BFBF-4F72-9AC5-510F41236EA5@microsoft.com... >> >> > Try the sample you find here: >> >> > http://msdn2.microsoft.com/en-US/library/system.data.datatable.parentrelations.aspx >> >> > >> >> > "Emre DYNÇER" wrote: >> >> > >> >> >> 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 >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> 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. Show quote "Emre DÃNÇER" wrote: > 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(); > > } > > } > > "MrSmersh" <MrSme***@discussions.microsoft.com> wrote in message > news:B627E65E-E904-4A82-8065-DCADD2CF5425@microsoft.com... > > 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. > > > > > > "Emre DYNÇER" wrote: > > > >> 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 > >> > >> > >> > >> > >> "MrSmersh" <MrSme***@discussions.microsoft.com> wrote in message > >> news:52B01D15-F793-4353-A32E-F624190134DA@microsoft.com... > >> > 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 > >> > > >> > "Emre DYNÇER" wrote: > >> > > >> >> 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 > >> >> "MrSmersh" <MrSme***@discussions.microsoft.com> wrote in message > >> >> news:F83BF6D0-BFBF-4F72-9AC5-510F41236EA5@microsoft.com... > >> >> > Try the sample you find here: > >> >> > http://msdn2.microsoft.com/en-US/library/system.data.datatable.parentrelations.aspx > >> >> > > >> >> > "Emre DYNÇER" wrote: > >> >> > > >> >> >> 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 > >> >> >> > >> >> >> > >> >> >> > >> >> > >> >> > >> >> > >> > >> > >> > > >  |
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