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Read data from database and store result to DataSet

I am trying to read data from a database and store it to DataSet as result. The point of this is that I want to create a Report in DevExpress which contains multiple parameter. When I store data to dataset I want to filter report based on User Input.
public void BindToData(int OrgId, bool Status)
{
try
{
string connString = #"Data Source=(LocalDb)\MSSQLLocalDB;Initial Catalog=DesignSaoOsig1;Integrated Security=True";
string strproc = "TestReport";
using (SqlDataAdapter sda = new SqlDataAdapter(strproc, connString))
{
sda.SelectCommand.CommandType = CommandType.StoredProcedure;
sda.SelectCommand.Parameters.Add("#Status", SqlDbType.Bit).Value = Status;
sda.SelectCommand.Parameters.Add("#OrgJed", SqlDbType.Int).Value = OrgId;
DataSet ds = new DataSet();
sda.Fill(ds);
XtraReport report = new XtraReport();
report.DataSource = ds;
}
}
catch (Exception)
{
throw;
}
}
Button click to run function
protected void Button1_Click(object sender, EventArgs e)
{
int OrgId = 1;
bool Status = true;
BindToData(OrgId,Status);
}
So far this is code which I wrote but when I run it report.DataSource = ds doesn't get any result.
When I debug it, I didn't see where the error is.
Stored Procedure
USE [DesignSaoOsig1]
GO
/****** Object: StoredProcedure [dbo].[TestReport] Script Date: 29. 5. 2020. 09:20:27 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE PROCEDURE [dbo].[TestReport]
(
#Status bit,
#OrgJed int
)
AS
BEGIN
SELECT TOP 1 OrgUnitID
FROM tblZaposleni_AD
--WHERE Status = #Status AND
-- OrgUnitID = #OrgJed
END

I have just run your exact code with a different connection string:
try
{
string connString = #"Confidential";
string strproc = "TestReport";
using (SqlDataAdapter sda = new SqlDataAdapter(strproc, connString))
{
sda.SelectCommand.CommandType = CommandType.StoredProcedure;
sda.SelectCommand.Parameters.Add("#Status", SqlDbType.Bit).Value = true;
sda.SelectCommand.Parameters.Add("#OrgJed", SqlDbType.Int).Value = 1;
DataSet ds = new DataSet();
sda.Fill(ds);
string temp = "123"; // Line to set breakpoint on
}
}
catch (Exception)
{
throw;
}
And it gives me a single table result with a single row as show in the watch window below:
Note in addition to selecting the id from a table I have selected the input parameters so they are visible and can be checked that what comes out is the same as what went in.

C# Windows Form using OracleDataAdapter to insert rows to a Oracle Table from a System DataTable

I'm writing a windows form that populates a DataTable and I want it to insert into an Oracle Table. I've seen some examples here that use the OracleDataAdapter to do this so I don't have to loop through all the records. The code doesn't have any errors but when I check the Table using Toad(I did refresh) I don't see it. I used the example below
Update and insert records into Oracle table using OracleDataAdapter from DataTable
Here is how my DataTable is made:
public DataTable dtMain = new DataTable();
public void FillTable(DataTable dt)
{
dtMain.Columns.Add("SERIAL", typeof(System.String));
dtMain.Columns.Add("LOCATION", typeof(System.String));
dtMain.Columns.Add("UPC", typeof(System.String));
dtMain.Columns.Add("PRODUCT", typeof(System.String));
dtMain.Columns.Add("CREATED_BY", typeof(System.String));
dtMain.Columns.Add("CREATED_DATE", typeof(System.DateTime));
dtMain.Columns.Add("SKU", typeof(System.String));
dtMain.Columns.Add("MAN_DATE", typeof(System.DateTime));
dtUpload.Columns[0].Unique = true;
dtMain.Merge(dt);
}
This is the how I'm trying to insert into the database
private void btnUpload_Click(object sender, EventArgs e)
{
DataTable dt = new DataTable();
string strSelect = "SELECT serial, upc, man_date, location, product, created_by, created_date, serial from schema.table where rownum < 2";
string strInsert = "INSERT INTO schema.table (serial, upc, man_date, location, product, created_by, created_date, serial) VALUES (:serial, :upc, :man_date, :location, :product, :created_by, :created_date, :serial)";
string conStr = ConfigurationManager.ConnectionStrings["connection"].ConnectionString;
OracleConnection connection = new OracleConnection(conStr);
connection.Open();
if (connection.State != ConnectionState.Open)
{
return;
}
try
{
OracleDataAdapter adapterS = new OracleDataAdapter();
adapterS.SelectCommand = new OracleCommand(strSelect, connection);
adapterS.Fill(dt);
dt.Rows.Remove(dt.Rows[0]);
dt.Merge(dtUpload);
}
catch (Exception ex)
{
string x = ex.Message + ex.StackTrace;
throw;
}
for (int i = 0; dt.Rows.Count > i; i++)
{
OracleDataAdapter adapter = new OracleDataAdapter();
adapter.InsertCommand = new OracleCommand(strInsert, connection);
adapter.InsertCommand.BindByName = true;
OracleParameter pSerial = new OracleParameter(":serial", OracleDbType.Varchar2);
pSerial.SourceColumn = dt.Columns[0].ColumnName;
pSerial.Value = dtUpload.Rows[i][0];
OracleParameter pLocation = new OracleParameter(":location", OracleDbType.Varchar2);
pLocation.SourceColumn = dt.Columns[1].ColumnName;
pLocation.Value = dtUpload.Rows[i][1];
OracleParameter pUPC = new OracleParameter(":upc", OracleDbType.Date);
pUPC.SourceColumn = dt.Columns[2].ColumnName;
pUPC.Value = dtUpload.Rows[i][2];
OracleParameter pProduct = new OracleParameter(":product", OracleDbType.Varchar2);
pProduct.SourceColumn = dt.Columns[3].ColumnName;
pProduct.Value = dtUpload.Rows[i][3];
OracleParameter pCreatedBy = new OracleParameter(":created_by", OracleDbType.Varchar2);
pCreatedBy.SourceColumn = dt.Columns[4].ColumnName;
pCreatedBy.Value = dtUpload.Rows[i][4];
OracleParameter pCreatedDate = new OracleParameter(":created_date", OracleDbType.Varchar2);
pCreatedDate.SourceColumn = dt.Columns[5].ColumnName;
pCreatedDate.Value = dtUpload.Rows[i][5];
OracleParameter pSKU = new OracleParameter(":SKU", OracleDbType.Date);
pSKU.SourceColumn = dt.Columns[6].ColumnName;
pSKU.Value = dtUpload.Rows[i][6];
OracleParameter pManDate = new OracleParameter(":man_date", OracleDbType.Varchar2);
pManDate.SourceColumn = dt.Columns[7].ColumnName;
pManDate.Value = dtUpload.Rows[i][7];
adapter.InsertCommand.Parameters.Add(pSerial);
adapter.InsertCommand.Parameters.Add(pLocation);
adapter.InsertCommand.Parameters.Add(pUPC);
adapter.InsertCommand.Parameters.Add(pProduct);
adapter.InsertCommand.Parameters.Add(pCreatedBy);
adapter.InsertCommand.Parameters.Add(pCreatedDate);
adapter.InsertCommand.Parameters.Add(pserial);
adapter.InsertCommand.Parameters.Add(pManDate);
}
try
{
adapter.Update(dt);
}
catch (Exception ex)
{
string x = ex.Message + ex.StackTrace;
throw;
}
connection.Close();
connection.Dispose();
}
If someone can give me some pointers that would be great, I've been Googling for 2 days and I just can't figure it out. I bet it's something simple
Update:
Thank you for the reply, it took me a bit to get back to this project. When I posted this I didn't realize I forgot to include my select statement.
For the OracleParameter value, I thought using SourceColumn would use that column for the values.
I did update the DataTable with the serial being unique. It still doesn't insert the data. If I included the Parameter.value would I have loop row by row to do this? Above I corrected/updated it with the current code.
Second Update:
Ok, I tried looping through the parameters to add the values from the DataTable, no errors but still not inserting in the database. I know my connectionstring is correct because the select query works. The code above has been updated for the changes I made. If some Oracle guru can shed some light on my problem a virtual high-five is waiting for them.

I never used OracleDataAdapter but I see these possible issues:
I don't think you can use OracleDataAdapter straight away, first you have to select an existing table from Oracle and based on this result you can do Update/Insert/Delete on it. Where is your strSelect string? I don't see it.
You created all the OracleParameter but I don't see that you assign any value to it, they are all empty. I would expect something like pOptoroLP.Value = ...; before you make any insert.
You should define a unique, resp. Primary Key column like dt.Columns["SERIAL"].Unique = true; in order to make Update() or Delete(). Maybe it is not required for Insert(), I don't know.
Did you follow the examples in Data Provider for .NET Developer's Guide

I finally found the problem, the row state in the DataTable needs to in the state of Added for it to work. If someone else has this problem here is my new code and you can compare it to what I was trying to do. Thank you Wernfried Domscheit for the Oracle part but it turned out to be my DataTable was the issue though setting the Unique column was probably an issue as well, I didn't check. The OracleCommandBuilder took care of the insert statements and parameters for me.
private void btnUpload_Click(object sender, EventArgs e)
{
DataTable dt = new DataTable();
string strSelect = "SELECT serial, upc, man_date, location, product, created_by, created_date, serial from schema.table where rownum < 2";
string strInsert = "INSERT INTO schema.table (serial, upc, man_date, location, product, created_by, created_date, serial) VALUES (:serial, :upc, :man_date, :location, :product, :created_by, :created_date, :serial)";
string conStr = ConfigurationManager.ConnectionStrings["connection"].ConnectionString;
OracleConnection connection = new OracleConnection(conStr);
connection.Open();
if (connection.State != ConnectionState.Open)
{
return;
}
OracleDataAdapter adapter = new OracleDataAdapter(strSelect, conStr);
OracleCommandBuilder builder = new OracleCommandBuilder(adapter);
adapter.Fill(dt);
dt.Columns["SERIAL"].Unique = true;
dt.Merge(dtUpload);
dt.Rows.Remove(dt.Rows[0]);
foreach (DataRow row in dt.Rows)
{
row.SetAdded();
}
try
{
adapter.Update(dt);
}
catch (Exception ex)
{
string x = ex.Message + ex.StackTrace;
throw;
}
finally
{
connection.Close();
connection.Dispose();
}
}

C# ASP.Net Processing Issue - Reading Table While Deleting Rows

Simply, I have an application that has one page that deletes and then re-adds/refreshes the records into a table every 30 seconds. I have another page that runs every 45 seconds that reads the table data and builds a chart.
The problem is, in the read/view page, every once in a while I get a 0 value (from a max count) and the chart shows nothing. I have a feeling that this is happening because the read is being done at the exact same time the delete page has deleted all the records in the table but has not yet refreshed/re-added them.
Is there a way in my application I can hold off on the read when the table is being refreshed?
Best Regards,
Andy
C#
ASP.Net 4.5
SQL Server 2012
My code below is run in an ASP.Net 4.5 built Windows service. It deletes all records in the ActualPlot table and then refreshes/adds new records from a text file every 30 seconds. I basically need to block (lock?) any user from reading the ActualPlot table while the records are being deleted and refreshed. Can you PLEASE help me change my code to do this?
private void timer1_Tick(object sender, ElapsedEventArgs e)
{
// Open the SAP text files, clear the data in the tables and repopulate the new SAP data into the tables.
var cnnString = ConfigurationManager.ConnectionStrings["TaktBoardsConnectionString"].ConnectionString;
SqlConnection conn = new SqlConnection(cnnString);
SqlConnection conndetail = new SqlConnection(cnnString);
SqlConnection connEdit = new SqlConnection(cnnString);
SqlCommand cmdGetProductFile = new SqlCommand();
SqlDataReader reader;
string sql;
// Delete all the records from the ActualPlot and the ActualPlotPreload tables. We are going to repopulate them with the data from the text file.
sql = "DELETE FROM ActualPlotPreload";
try
{
conn.Open();
SqlCommand cmd = new SqlCommand(sql, conn);
cmd.ExecuteNonQuery();
}
catch (System.Data.SqlClient.SqlException ex)
{
string msg = "Delete Error:";
msg += ex.Message;
Library.WriteErrorLog(msg);
}
finally
{
conn.Close();
}
sql = "DELETE FROM ActualPlot";
try
{
conn.Open();
SqlCommand cmd = new SqlCommand(sql, conn);
cmd.ExecuteNonQuery();
}
catch (System.Data.SqlClient.SqlException ex)
{
string msg = "Delete Error:";
msg += ex.Message;
Library.WriteErrorLog(msg);
}
finally
{
conn.Close();
}
// Read the SAP text file and load the data into the ActualPlotPreload table
sql = "SELECT DISTINCT [BoardName], [ProductFile], [ProductFileIdent] FROM [TaktBoards].[dbo].[TaktBoard] ";
sql = sql + "JOIN [TaktBoards].[dbo].[Product] ON [Product].[ProductID] = [TaktBoard].[ProductID]";
cmdGetProductFile.CommandText = sql;
cmdGetProductFile.CommandType = CommandType.Text;
cmdGetProductFile.Connection = conn;
conn.Open();
reader = cmdGetProductFile.ExecuteReader();
string DBProductFile = "";
string DBTischID = "";
string filepath = "";
string[] cellvalues;
DateTime dt, DateCheckNotMidnightShift;
DateTime ldSAPFileLastMod = DateTime.Now;
string MyDateString;
int FileRecordCount = 1;
while (reader.Read())
{
DBProductFile = (string)reader["ProductFile"];
DBTischID = (string)reader["ProductFileIdent"];
filepath = "c:\\inetpub\\wwwroot\\WebApps\\TaktBoard\\FilesFromSAP\\" + DBProductFile;
FileInfo fileInfo = new FileInfo(filepath); // Open file
ldSAPFileLastMod = fileInfo.LastWriteTime; // Get last time modified
try
{
StreamReader sr = new StreamReader(filepath);
FileRecordCount = 1;
// Populate the AcutalPlotPreload table from with the dates from the SAP text file.
sql = "INSERT into ActualPlotPreload (ActualDate, TischID) values (#ActualDate, #TischID)";
while (!sr.EndOfStream)
{
cellvalues = sr.ReadLine().Split(';');
if (FileRecordCount > 1 & cellvalues[7] != "")
{
MyDateString = cellvalues[7];
DateTime ldDateCheck = DateTime.ParseExact(MyDateString, "M/dd/yyyy", null);
DateTime dateNow = DateTime.Now;
string lsDateString = dateNow.Month + "/" + dateNow.Day.ToString("d2") + "/" + dateNow.Year;
DateTime ldCurrentDate = DateTime.ParseExact(lsDateString, "M/dd/yyyy", null);
string lsTischID = cellvalues[119];
if (ldDateCheck == ldCurrentDate)
{
try
{
conndetail.Open();
SqlCommand cmd = new SqlCommand(sql, conndetail);
cmd.Parameters.Add("#ActualDate", SqlDbType.DateTime);
cmd.Parameters.Add("#TischID", SqlDbType.VarChar);
cmd.Parameters["#TischID"].Value = cellvalues[119];
MyDateString = cellvalues[7] + " " + cellvalues[55];
dt = DateTime.ParseExact(MyDateString, "M/dd/yyyy H:mm:ss", null);
cmd.Parameters["#ActualDate"].Value = dt;
// Ignore any midnight shift (12am to 3/4am) units built.
DateCheckNotMidnightShift = DateTime.ParseExact(cellvalues[7] + " 6:00:00", "M/dd/yyyy H:mm:ss", null);
if (dt >= DateCheckNotMidnightShift)
{
cmd.ExecuteNonQuery();
}
}
catch (System.Data.SqlClient.SqlException ex)
{
string msg = "Insert Error:";
msg += ex.Message;
Library.WriteErrorLog(msg);
}
finally
{
conndetail.Close();
}
}
}
FileRecordCount++;
}
sr.Close();
}
catch
{ }
finally
{ }
}
conn.Close();
// Get the unique TischID's and ActualDate from the ActualPlotPreload table. Then loop through each one, adding the ActualUnits
// AcutalDate and TischID to the ActualPlot table. For each unique TischID we make sure that we reset the liTargetUnits to 1 and
// count up as we insert.
SqlCommand cmdGetTischID = new SqlCommand();
SqlDataReader readerTischID;
int liTargetUnits = 0;
string sqlInsert = "INSERT into ActualPlot (ActualUnits, ActualDate, TischID) values (#ActualUnits, #ActualDate, #TischID)";
sql = "SELECT DISTINCT [ActualDate], [TischID] FROM [TaktBoards].[dbo].[ActualPlotPreload] ORDER BY [TischID], [ActualDate] ASC ";
cmdGetTischID.CommandText = sql;
cmdGetTischID.CommandType = CommandType.Text;
cmdGetTischID.Connection = conn;
conn.Open();
readerTischID = cmdGetTischID.ExecuteReader();
DBTischID = "";
DateTime DBActualDate;
string DBTischIDInitial = "";
while (readerTischID.Read())
{
DBTischID = (string)readerTischID["TischID"];
DBActualDate = (DateTime)readerTischID["ActualDate"];
if (DBTischIDInitial != DBTischID)
{
liTargetUnits = 1;
DBTischIDInitial = DBTischID;
}
else
{
liTargetUnits++;
}
try
{
conndetail.Open();
SqlCommand cmd = new SqlCommand(sqlInsert, conndetail);
cmd.Parameters.Add("#ActualUnits", SqlDbType.Real);
cmd.Parameters.Add("#ActualDate", SqlDbType.DateTime);
cmd.Parameters.Add("#TischID", SqlDbType.VarChar);
cmd.Parameters["#TischID"].Value = DBTischID;
cmd.Parameters["#ActualDate"].Value = DBActualDate;
cmd.Parameters["#ActualUnits"].Value = liTargetUnits;
cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
}
catch (System.Data.SqlClient.SqlException ex)
{
string msg = "Insert Error:";
msg += ex.Message;
Library.WriteErrorLog(msg);
}
finally
{
conndetail.Close();
}
}
conn.Close();
Library.WriteErrorLog("SAP text file data has been imported.");
}

If the data is being re-added right back after the delete (basically you know what to re-add before emptying the table), you could have both operation within the same SQL transaction, so that the data will be available to the other page only when it has been re-added.
I mean something like that :
public bool DeleteAndAddData(string connString)
{
using (OleDbConnection conn = new OleDbConnection(connString))
{
OleDbTransaction tran = null;
try
{
conn.Open();
tran = conn.BeginTransaction();
OleDbCommand deleteComm = new OleDbCommand("DELETE FROM Table", conn);
deleteComm.ExecuteNonQuery();
OleDbCommand reAddComm = new OleDbCommand("INSERT INTO Table VALUES(1, 'blabla', 'etc.'", conn);
reAddComm.ExecuteNonQuery();
tran.Commit();
}
catch (Exception ex)
{
tran.Rollback();
return false;
}
}
return true;
}

If your queries don't take too long to execute, you can start the two with a difference of 7.5 seconds, as there is a collision at every 90 seconds when the read/write finishes 3 cycles, and read/view finishes 2 cycles.
That being said, it's not a fool-proof solution, just a trick based on assumptions, in case you wan't to be completely sure that read/view never happens when read/write cycle is happening, try considering having a Read Lock. I would recommend reading Understanding how SQL Server executes a query and Locking in the Database Engine
Hope that helps.

I would try a couple of things:
Make sure your DELETE + INSERT operation is occurring within a single transaction:
BEGIN TRAN
DELETE FROM ...
INSERT INTO ...
COMMIT
If this isn't a busy table, try locking hints your SELECT statement. For example:
SELECT ...
FROM Table
WITH (UPDLOCK, HOLDLOCK)
In the case where the update transactions starts while your SELECT statement is running, this will cause that transaction to wait until the SELECT is finished. Unfortunately it will block other SELECT statements too, but you don't risk reading dirty data.

I was not able to figure this out but I changed my code so the program was not deleting all the rows in the ActualPlot table but checking to see if the row was there and if not adding the new row from the text file.

Unidata UniObjects for .NET - Write amendments back to unidata from modified table

I'm trying to write data back into a file on Unidata, after the contents have been adjusted in a datagridview.
I've tried various option based around the code below, but with no luck.
Within the foreach section I want to update my file.
The file consists of 10 single value attributes.
I tried fl.write(),but get an error relating to writing to a null value...
try
{
DataTable modifiedTable = m_DS.Tables[0].GetChanges(DataRowState.Modified);
if (modifiedTable.Rows.Count > 0)
{
U2Connection con = GetConnection();
Console.WriteLine("Connected.................");
UniSession lUniSession = con.UniSession;
UniFile fl = lUniSession.CreateUniFile("myTableName");
UniDynArray udr3 = new UniDynArray(lUniSession);
foreach (DataRow item in modifiedTable.Rows)
{
}
con.Close();
}
}

Thank you for using UniObjects’s API of U2 Toolkit for .NET (formerly known as standalone UO.NET).
Yesterday (June 10th, 2014) , we have Released U2 Toolkit for .NET v2.1.0. Main features of U2 Toolkit for .NET v2.1.0 is
Native Visual Studio Integration
For other features, see this link
http://blog.rocketsoftware.com/2014/05/access-nosql-data-using-sql-syntax-u2-toolkit-net-v2-1-0-beta/
Can you please try the same code ( 10 single value attributes) using SELECT and UPDATE. For your information, SELECT and UPDATE behind the scene calls UniFile Read and Write. These Samples are part of the installation. Go to these directories.
C:\Program Files (x86)\Rocket Software\U2 Toolkit for .NET\U2 Database Provider\samples\C#\UniData\NativeAccess\Select_SQL_Syntax
C:\Program Files (x86)\Rocket Software\U2 Toolkit for .NET\U2 Database Provider\samples\C#\UniData\NativeAccess\Update_SQL_Syntax
SELECT
private static void Select()
{
try
{
Console.WriteLine(Environment.NewLine + "Start...");
ConnectionStringSettingsCollection settings = ConfigurationManager.ConnectionStrings;
ConnectionStringSettings cs = settings["u2_connection"];
U2Connection lConn = new U2Connection();
lConn.ConnectionString = cs.ConnectionString;
lConn.Open();
Console.WriteLine("Connected...");
U2Command cmd = lConn.CreateCommand();
//ID,FNAME,LNAME : Single Value
//SEMESTER: Multi Value
//COURSE_NBR,COURSE_GRD: MS
cmd.CommandText = string.Format("SELECT ID,FNAME,LNAME,SEMESTER,COURSE_NBR,COURSE_GRD FROM STUDENT WHERE ID > 0 ORDER BY ID");
U2DataAdapter da = new U2DataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds);
Console.WriteLine(Environment.NewLine);
ds.WriteXml(Console.Out);
lConn.Close();
Console.WriteLine(Environment.NewLine + "End...");
Console.WriteLine(SUCCESS_MSG);
}
catch (Exception e2)
{
string lErr = e2.Message;
if (e2.InnerException != null)
{
lErr += lErr + e2.InnerException.Message;
}
Console.WriteLine(Environment.NewLine + lErr);
Console.WriteLine(FAIL_MSG);
}
}
Update
private static void Update_Using_DataSet()
{
try
{
Console.WriteLine(Environment.NewLine + "Start...");
ConnectionStringSettingsCollection settings = ConfigurationManager.ConnectionStrings;
ConnectionStringSettings cs = settings["u2_connection"];
U2Connection lConn = new U2Connection();
lConn.ConnectionString = cs.ConnectionString;
lConn.Open();
Console.WriteLine("Connected...");
U2Command cmd = lConn.CreateCommand();
//ID,FNAME,LNAME : Single Value
//SEMESTER: Multi Value
//COURSE_NBR,COURSE_GRD: MS
cmd.CommandText = string.Format("SELECT ID,FNAME,LNAME,SEMESTER,COURSE_NBR,COURSE_GRD FROM STUDENT WHERE ID={0} ORDER BY ID",ID);
U2DataAdapter da = new U2DataAdapter(cmd);
U2CommandBuilder builder = new U2CommandBuilder(da);
da.UpdateCommand = builder.GetUpdateCommand();
DataSet ds = new DataSet();
da.Fill(ds);
DataTable dt = ds.Tables[0];
DataRowCollection lDataRowCollection = dt.Rows;
int i = 1;
foreach (DataRow item in lDataRowCollection)
{
item["FNAME"] = item["FNAME"] + "3";// modify single value
item["SEMESTER"] = item["SEMESTER"] + "$";//modify multi-value
item["COURSE_GRD"] = item["COURSE_GRD"] + "$";
i++;
}
da.Update(ds);//use DataAdapter's Update() API
//print modified value
cmd.CommandText = string.Format("SELECT ID,FNAME,LNAME,SEMESTER,COURSE_NBR,COURSE_GRD FROM STUDENT WHERE ID={0} ORDER BY ID", ID); ;
//verify the change
U2DataAdapter da2 = new U2DataAdapter(cmd);
DataSet ds2 = new DataSet();
da2.Fill(ds2);
Console.WriteLine(Environment.NewLine);
ds2.WriteXml(Console.Out);
//close connection
lConn.Close();
Console.WriteLine(Environment.NewLine + "End...");
Console.WriteLine(SUCCESS_MSG);
}
catch (Exception e2)
{
Console.WriteLine(FAIL_MSG);
string lErr = e2.Message;
if (e2.InnerException != null)
{
lErr += lErr + e2.InnerException.Message;
}
Console.WriteLine(Environment.NewLine + lErr);
}
}

You will need to modify the UniDynArray (the record) for each row value in the table and then write the UniDynArray to the file and specific record id:
for (Int32 i=0; i < modifiedTable.Rows.Count; i++)
{
DataRow item = modifiedTable.Rows[i];
//Modify each attribute in the record from the rows in the table
udr3.Replace(i+1, (String)item[0]);
}
//Write the modified record to the file
fl.Write("MyRecordId", udr3);
The reason you got the null reference exception is because you didn't assign a value to fl.RecordId or fl.Record before calling fl.Write(). As you can see above, I prefer to use the overload of the Write method that takes record id and record data as parameters instead of setting the properties on the instance of UniFile.

How to count the number of rows and display it

I am working on a desktop application that returns list of tables that have foreign keys in a datagrid by this function.
public void GetPrimaryKeyTable()
{
//An instance of the connection string is created to manage the contents of the connection string.
var sqlConnection = new SqlConnectionStringBuilder();
sqlConnection.DataSource = "192.168.10.3";
sqlConnection.UserID = "gp";
sqlConnection.Password = "gp";
sqlConnection.InitialCatalog = Convert.ToString(cmbDatabases.SelectedValue);
string connectionString = sqlConnection.ConnectionString;
SqlConnection sConnection = new SqlConnection(connectionString);
//To Open the connection.
sConnection.Open();
//Query to select the table_names that have PRIMARY_KEYS.
string selectPrimaryKeys = #"SELECT
TABLE_NAME
FROM
INFORMATION_SCHEMA.TABLE_CONSTRAINTS
WHERE
CONSTRAINT_TYPE = 'PRIMARY KEY'
AND
TABLE_NAME <> 'dtProperties'
ORDER BY
TABLE_NAME";
//Create the command object
SqlCommand sCommand = new SqlCommand(selectPrimaryKeys, sConnection);
try
{
//Create the dataset
DataSet dsListOfPrimaryKeys = new DataSet("INFORMATION_SCHEMA.TABLE_CONSTRAINTS");
//Create the dataadapter object
SqlDataAdapter sDataAdapter = new SqlDataAdapter(selectPrimaryKeys, sConnection);
//Provides the master mapping between the sourcr table and system.data.datatable
sDataAdapter.TableMappings.Add("Table", "INFORMATION_SCHEMA.TABLE_CONSTRAINTS");
//Fill the dataset
sDataAdapter.Fill(dsListOfPrimaryKeys);
//Bind the result combobox with primary key tables
DataViewManager dvmListOfPrimaryKeys = dsListOfPrimaryKeys.DefaultViewManager;
dgResultView.DataSource = dsListOfPrimaryKeys.Tables["INFORMATION_SCHEMA.TABLE_CONSTRAINTS"];
}
catch(Exception ex)
{
//All the exceptions are handled and written in the EventLog.
EventLog log = new EventLog("Application");
log.Source = "MFDBAnalyser";
log.WriteEntry(ex.Message);
}
finally
{
//If connection is not closed then close the connection
if(sConnection.State != ConnectionState.Closed)
{
sConnection.Dispose();
}
}
}
Now I want to count the number of tables that fall in this category and display it in a lablel that this much of tables are under this category..
Can you guys please help me

I believe you can just use the DataSet.Tables.Count method.
http://msdn.microsoft.com/en-us/library/system.data.internaldatacollectionbase.count.aspx
Or, DataSet.Tables[i].Rows.Count