sql - Error when executing insertion query -

how avoid duplicate data before inserting. used below code i'm getting error.

no column name specified column 1 of 'temp'.

no column name specified column 2 of 'temp'.

no column name specified column 3 of 'temp'.

no column name specified column 4 of 'temp'.

no column name specified column 5 of 'temp'.

no column name specified column 6 of 'temp'.

no column name specified column 8 of 'temp'.

no column name specified column 9 of 'temp'.

invalid column name 'datelist'.

  using (sqlconnection con2 = new sqlconnection(configurationmanager.connectionstrings["connectionstring"].connectionstring))         {             var fromdate = datetime.parse(txtfromdate.text);             var todate = datetime.parse(txttodate.text);             var datedif1 = (todate - fromdate).days;              var sqlinsert = new sqlcommand("insert datelist ([datedif],[batch],[daywk],[semester],[weekbatch],[subject],[facultyname],[facultyid],[weekmonth])  select * (select @datedif,@batch,@daywk,@semester,@weekbatch,@subject,@facultyname,@facultyid,@weekmonth) temp not exists (select datelist,batch datelist batch=@batch , datedif=@datedif)", con2);              var sqlparamater = sqlinsert.parameters.add("@datedif", sqldbtype.date);             var sqlparameter1 = sqlinsert.parameters.add("@batch", sqldbtype.nvarchar);             var sqlparameter2 = sqlinsert.parameters.add("@daywk", sqldbtype.nvarchar);             var sqlparameter3 = sqlinsert.parameters.add("@semester", sqldbtype.nvarchar);             var sqlparameter4 = sqlinsert.parameters.add("@weekbatch", sqldbtype.nvarchar);             var sqlparameter5 = sqlinsert.parameters.add("@subject", sqldbtype.nvarchar);             var sqlparameter6 = sqlinsert.parameters.add("@facultyname", sqldbtype.nvarchar);             var sqlparameter7 = sqlinsert.parameters.add("@facultyid", sqldbtype.nvarchar);             var sqlparameter8 = sqlinsert.parameters.add("@weekmonth", sqldbtype.nvarchar);              con2.open();            // try             //{                 (var = 0; <= datedif1; i++)                 {                     var consecutivedate = fromdate.adddays(i);                      sqlparamater.value  = consecutivedate;                     sqlparameter1.value = batch1;                     sqlparameter2.value = dayweek;                     sqlparameter3.value = semester;                     sqlparameter4.value = weekbatch;                     sqlparameter5.value = subject;                     sqlparameter6.value = faculty;                     sqlparameter7.value = facultyid;                     sqlparameter8.value = weekmonth;                      int s = sqlinsert.executenonquery();                 }              } 

i'll admit not having tested this, given error message, subquery:

select      @datedif,     @batch,     -- , on     @weekmonth ) temp 

needs have column names defined, value comes variable.

that be:

select      @datedif datedif,     @batch batch,     -- , on     @weekmonth weekmonth ) temp