UpdateCommand

Question

what is wrong here? no error shows and nothing happens (the variables are not empty - I checked)

SqlCommand postname = new SqlCommand("UPDATE sites SET username=@username, userpass=@userpass WHERE useralias=@useralias",connection);
connection.Open();
SqlDataAdapter posttext = new SqlDataAdapter();
postname.Parameters.Add("@username", SqlDbType.NVarChar, 50, username);
postname.Parameters.Add("@userpass", SqlDbType.NVarChar, 50, userpass);
postname.Parameters.Add("@useralias", SqlDbType.NVarChar, 50, theAlias);
posttext.UpdateCommand = postname;

or am I not doing? I need to update the column to other values??.
I translated the interpreter, so I apologize if poorly understood.

Vulpes · Answer

As there's no error my suspicion is that it can't find the correct record to update and so does nothing. As there doesn't appear to be a primary key for your table I'd try setting one - username perhaps.

Dorababu Meka · Answer

Can you debug and post if any errors or exception you are getting

blase satiate · Answer

>Change all the datatypes to Varchar yes i do it - not happened the same problem. I write to the database like this:  qwerty and asdfg

Suthish Nair · Answer

Why using NVarchar (The N in NVARCHAR means uNicode.) Change all the datatypes to Varchar. Equal operator is incompatible with text ntext or image data types only.

Suthish Nair · Answer

try.. connection.Open(); SqlCommand postname = new SqlCommand(UPDATE sites SET username=@username userpass=@userpass WHERE useralias=@useraliasconnection); SqlDataAdapter posttext = new SqlDataAdapter(); postname.Parameters.Add(@username SqlDbType.NVarChar 50 username); postname.Parameters.Add(@userpass SqlDbType.NVarChar 50 userpass); postname.Parameters.Add(@useralias SqlDbType.NVarChar 50 useralias); posttext.UpdateCommand = postname; Put a breakpoint and check the parameters value. Also check the Select statement for above updation

Satish Bhat · Answer

To post the data modification to the database you have to call the Update method of the dataadapter which you've not done. And before that there has to be changes in the dataset/datatable in the dataadapter. Otherwise you can call posttext.UpdateCommand = postname; posttext.UpdateCommand.ExecuteNonQuery() ;

shams khan · Answer

i think this will work for u.check it out please try.. connection.Open(); SqlCommand postname = new SqlCommand(UPDATE sites SET username=@username userpass=@userpass WHERE useralias=@useraliasconnection); SqlDataAdapter posttext = new SqlDataAdapter(); postname.Parameters.Add(@username SqlDbType.NVarChar 50 username); postname.Parameters.Add(@userpass SqlDbType.NVarChar 50 userpass); postname.Parameters.Add(@useralias SqlDbType.NVarChar 50 useralias); posttext.UpdateCommand = postname; } catch(Exceptio ex) { MessageBox.Show(ex.Message.ToString()); } also use the break point to detect error exactly if found if a problem in this code

blase satiate · Answer

id create column: 'id' type: 'int' and set primary key it. update it by this query: UPDATE sites SET username='test' userpass='test2' WHERE useralias='qiq' not work(( full code: using (SqlConnection connection = new SqlConnection(Data Source=.\SQLEXPRESS;AttachDbFilename=C:\Documents and Settings\stite\??? ?????????\visual studio 2010\Projects\WebApplication5\WebApplication5\App_Data\Database1.mdf;Integrated Security=True;User Instance=True;)) { //UPDATE connection.Open(); SqlCommand postname = new SqlCommand(UPDATE sites SET username='test' userpass='test2' WHERE useralias='qiq' connection); SqlDataAdapter posttext = new SqlDataAdapter(); posttext.UpdateCommand = postname; //end UPDATE //SELECT SqlCommand getname = new SqlCommand(SELECT usersite username userpass FROM sites WHERE useralias=' + theTable + ' connection); SqlDataReader gettext = getname.ExecuteReader(); while(gettext.Read()) { siteLabel.Text = String.Format(New auth for {0}: gettext[0]); loginLabel.Text = String.Format({0} gettext[1]); passLabel.Text = String.Format({0} gettext[2]); } gettext.Close(); //end SELECT }

blase satiate · Answer

not have error

blase satiate · Answer

using (SqlConnection connection = new SqlConnection(...)) { //UPDATE connection.Open(); SqlCommand postname = new SqlCommand(UPDATE sites SET username='+username+' userpass='+userpass+' WHERE useralias='+theTable+' connection); SqlDataAdapter posttext = new SqlDataAdapter(); posttext.UpdateCommand = postname; //end UPDATE //SELECT SqlCommand getname = new SqlCommand(SELECT usersite username userpass FROM sites WHERE useralias=' + theTable + ' connection); SqlDataReader gettext = getname.ExecuteReader(); while(gettext.Read()) { siteLabel.Text = String.Format(New auth for {0}: gettext[0]); loginLabel.Text = String.Format({0} gettext[1]); passLabel.Text = String.Format({0} gettext[2]); } gettext.Close(); //end SELECT }

blase satiate · Answer

type NVarChar is default i must change it? on what? connection.Open(); SqlCommand postname = new SqlCommand(UPDATE sites SET username='+username+' userpass='+userpass+' WHERE useralias='+theTable+' connection); SqlDataAdapter posttext = new SqlDataAdapter(); postname.Parameters.Add(@username SqlDbType.NVarChar 50 username); // del it postname.Parameters.Add(@userpass SqlDbType.NVarChar 50 userpass); //del it postname.Parameters.Add(@useralias SqlDbType.NVarChar 50 theTable); //del it posttext.UpdateCommand = postname; LGN.Text = username; PSW.Text = userpass; I deleted these parameters. and changed in a database of these types of data to Varchar totext to ntext - nothing happened. what should be changed?

Suthish Nair · Answer

I got confused now. Its working now or still facing the problem. Because you unchecked the Accepted Answer.

Suthish Nair · Answer

check the datatypes - NVarChar. theTable - what and how the value coming. try hard coding an update statement with values.

blase satiate · Answer

>Now its working fine updation happening? yes.. UPDATE code is not correct i see : all is correct but all is not work. only SELECT good work. PS: >SELECT works well. shows the values ??from the table that there are correctly write*: SELECT works well. shows the values ?? from the table that there are*

Suthish Nair · Answer

Now its working fine updation happening?

blase satiate · Answer

nothing. Values is not empty. Full code: using ( SqlConnection connection = new SqlConnection ( Data Source=.\SQLEXPRESS;AttachDbFilename=....;Integrated Security=True;User Instance=True; )) { //UPDATE connection.Open(); SqlCommand postname = new SqlCommand ( UPDATE sites SET username=@username userpass=@userpass WHERE useralias=@useralias  connection); SqlDataAdapter posttext = new SqlDataAdapter (); postname.Parameters.Add( @username  SqlDbType .NVarChar 50 username); postname.Parameters.Add(  @userpass  SqlDbType .NVarChar 50 userpass); postname.Parameters.Add( @useralias  SqlDbType .NVarChar 50 theTable); posttext.UpdateCommand = postname; LGN.Text = username; PSW.Text = userpass; //check values //SELECT SqlCommand getname = new SqlCommand ( SELECT usersite username userpass FROM sites WHERE useralias=' + theTable + '  connection); SqlDataReader gettext = getname.ExecuteReader(); while (gettext.Read()) { siteLabel.Text = String .Format( New auth for {0}:  gettext[0]); loginLabel.Text = String .Format( {0}  gettext[1]); passLabel.Text = String .Format( {0}  gettext[2]); } gettext.Close(); } in the db table Sites has not changed . SELECT works well. shows the values ??from the table that there are