Develop Reference

using one button to insert and update different db tables

I am using the same button "Save" to update a table called AnalysisExperiments and also to insert data into a table called "Analysis". however the update is not working. Here is the code:
#region Insert Data into Analysis Table
if (checkIfRepeatedJobNumber(tbJobNumber.Text.Trim()))
{
MessageBox.Show("Job Number is already exist.", "Repeated Data");
return;
}
string query = "insert into Analysis (ID, WellName, EstimatedStartDate, SOWComments, ProgressComments, Field, FocalPoint, StudyCompleted, Company, ReservoirPressure, ReservoirTemp, SelectedSamples) " +
"values (#ID, #WellName, #SamplingDate, #SOWComments, #ProgressComments, #Field, #FocalPoint, #StudyCompleted, #Company, #ReservoirPressure, #ReservoirTemp, #SelectedSamples)";
OleDbCommand cmd = new OleDbCommand(query, conn);
cmd.Parameters.AddWithValue("#ID", tbJobNumber.Text);
cmd.Parameters.AddWithValue("#WellName", tbWellName.Text);
cmd.Parameters.AddWithValue("#SamplingDate", dtpSamplingDate.Text);
cmd.Parameters.AddWithValue("#SOWComments", tbSOW_Comments.Text);
cmd.Parameters.AddWithValue("#ProgressComments", tbProgressComments.Text);
cmd.Parameters.AddWithValue("#Field", tbFieldName.Text);
cmd.Parameters.AddWithValue("#FocalPoint", tbFocalName.Text);
if (radYes.Checked)
cmd.Parameters.AddWithValue("#StudyCompleted", "Yes");
else
cmd.Parameters.AddWithValue("#StudyCompleted", "No");
cmd.Parameters.AddWithValue("#Company", tbCompany.Text);
cmd.Parameters.AddWithValue("#ReservoirPressure", tbReservoirPressure.Text);
cmd.Parameters.AddWithValue("#ReservoirTemp", tbReservoirTemp.Text);
cmd.Parameters.AddWithValue("##SelectedSamples", tbSelectedSamples.Text);
try
{
conn.Open();
int j = cmd.ExecuteNonQuery();
if (j == 1)
{
MessageBox.Show("Done");
this.Close();
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
finally
{
conn.Close();
}
#endregion
#region update analysis Exp but still no working
#region Update database
try
{ int k = 0;
OleDbDataAdapter da;
da = new OleDbDataAdapter("select* from [AnalysisExperiments]", conn);
string ExpQuery = "update AnalysisExperiments set SampleNumber = #SampleNumber, Status = #Status where ID = '" + tbJobNumber.Text + "' and Experiment = '";
foreach (DataGridViewRow row in dgvExperiments.Rows)
{
ExpQuery += row.Cells["Experiment"].Value.ToString() + "'";
OleDbCommand updateCommand = new OleDbCommand(ExpQuery, conn);
updateCommand.Parameters.Add("#SampleNumber", OleDbType.VarWChar);
MessageBox.Show(row.Cells["SampleNumber"].Value.ToString() + " | " + row.Cells["Status"].Value.ToString() + " | " + row.Cells["Experiment"].Value.ToString());
updateCommand.Parameters["#SampleNumber"].Value = row.Cells["SampleNumber"].Value.ToString();
updateCommand.Parameters.Add("#Status", OleDbType.Boolean);
updateCommand.Parameters["#Status"].Value = row.Cells["Status"].Value;
da.UpdateCommand = updateCommand;
conn.Open();
k = da.UpdateCommand.ExecuteNonQuery();
conn.Close();
}
if (k == 1)
MessageBox.Show("Done");
else
{
MessageBox.Show("Nothing Updated!");
}
}
catch(Exception ex)
{
MessageBox.Show(ex.Message);
}
#endregion
#endregion
knowing that the compiler skips the loop in the update region.

At the second loop the query syntax becomes invalid cause the += that concatenates the previous text with the new one
Dim newQuery = ExQuery + row.Cells["Experiment"].Value.ToString() + "'";
And then use the new string for the ExecuteNonQuery.
Still this approach has many problems. You should separate this code in different methods and use parameters also for the last value

Have you tried to debug the foreach line to see if there are any rows in your dgvExperiments and if they are of type (or subtype of) DataGridViewRow ?

If there is no row in database sum command return an error

An error is thrown when there is no data in data base while converting a string value into int.
try {
SqlCommand cmdc = new SqlCommand("SELECT SUM(Credited_amount) FROM IMS_Credit_Dir WHERE Credit_comp_id=1 AND Crdt_typ_id=1", con);
string companya_credit_amount = null, comapnyb_credit_amount = null;
con.Open();
SqlDataReader drc = cmdc.ExecuteReader();
if (drc.HasRows)
{
while (drc.Read())
{
companya_credit_amount = drc[0].ToString();
}
drc.Close();
con.Close();
}
SqlCommand cmdcp = new SqlCommand("SELECT SUM(Credited_amount) FROM IMS_Credit_Dir WHERE Credit_comp_id=2 AND Crdt_typ_id=1", con);
con.Open();
SqlDataReader drcp = cmdcp.ExecuteReader();
if (drcp.HasRows)
{
while (drcp.Read())
{
companyb_credit_amount = drcp[0].ToString();
}
drcp.Close();
con.Close();
}
if (!Page.IsPostBack)
{
int companyA = 0,companyB=0;
if (companya_credit_amount != "") { companyA = Convert.ToInt32(credit_amount.ToString()); }
if (companyb_credit_amount != ""){ companyB = Convert.ToInt32(companyb_credit_amount); }
int total = (companyA+companyB);
count_total_lbl.Text = "Rs." + " " + total.ToString();
count_comapnya_lbl.Text = "Rs." + " " + companya_credit_amount.ToString();
count_companyb_lbl.Text ="Rs."+" "+ companyb_credit_amount.ToString();
}
}
catch(Exception ex) { Label2.Text = ex.ToString(); }
If there is value its working fine.but when there is no value in data base there is an error msg.
System.FormatException: Input string was not in a correct format.

Use IsDBNull to check for null values
Create and destroy all your type instances that implement IDisposable in using blocks. This ensures that connections are always released and resources are cleaned up.
Do not use connections across a class. Create them when needed and then dispose of them. Sql Server will handle connection pooling.
Get the native types directly, not the string equivalent! See changes to GetInt32 instead of ToString on the data reader.
You should refactor this to use SqlParameter's and make the retrieval statement generic OR get both SUM values in 1 sql call.
There is an if (!Page.IsPostBack) statement, if none of this code does anything if it is a postback then check at the top of the page and do not execute the sql statements if it is a postback. Otherwise the code is making (possibly) expensive sql calls for no reason.
try
{
int companyA = 0,companyB=0;
using(var con = new SqlConnection("connectionStringHere"))
{
con.Open();
using(SqlCommand cmdc = new SqlCommand("SELECT SUM(Credited_amount) FROM IMS_Credit_Dir WHERE Credit_comp_id=1 AND Crdt_typ_id=1", con))
using(SqlDataReader drc = cmdc.ExecuteReader())
{
if (drc.Read() && !drc.IsDBNull(0))
companyA = drc.GetInt32(0);
}
using(SqlCommand cmdcp = new SqlCommand("SELECT SUM(Credited_amount) FROM IMS_Credit_Dir WHERE Credit_comp_id=2 AND Crdt_typ_id=1", con))
using(SqlDataReader drcp = cmdcp.ExecuteReader())
{
if (drcp.Read() && !drcp.IsDBNull(0))
companyB = drcp.GetIn32(0);
}
}
// if you are not going to do anything with these values if its not a post back move the check to the top of the method
// and then do not execute anything if it is a postback
// ie: // if (Page.IsPostBack) return;
if (!Page.IsPostBack)
{
int total = (companyA+companyB);
count_total_lbl.Text = "Rs." + " " + total.ToString();
count_comapnya_lbl.Text = "Rs." + " " + companyA.ToString();
count_companyb_lbl.Text ="Rs."+" "+ companyB.ToString();
}
}
catch(Exception ex) { Label2.Text = ex.ToString(); }

Try to replace this
SELECT SUM(Credited_amount)
WITH
SELECT ISNULL(SUM(Credited_amount),0)
Also find one confusing code while converting Credited amount values
if (companya_credit_amount != "") { companyA = Convert.ToInt32(credit_amount.ToString()); }
---------^^^^^
if (companyb_credit_amount != ""){ companyB = Convert.ToInt32(companyb_credit_amount); }
I don't know about your business requirement but What i think Instead of using credit_amount value companya_credit_amount should be use to show value for companyA variable right?

You should do 2 things:
string companya_credit_amount = "", comapnyb_credit_amount = "";
Before assigning the value to these string variable you should check for db null as following:
while (drc.Read())
{
companya_credit_amount = (drc[0] != DbNull.Value) ? drc[0].ToString() : "" ;
}
Similarely
while (drcp.Read())
{
companyb_credit_amount = (drcp[0] != DbNull.Value) ? drcp[0].ToString() : "";
}
Try it.

You need to initialize credit_amount to empty and check if db value is null as shown below:
try {
companya_credit_amount = string.Empty;
companyb_credit_amount = string.Empty;
SqlCommand cmdc = new SqlCommand("SELECT SUM(Credited_amount) FROM IMS_Credit_Dir WHERE Credit_comp_id=1 AND Crdt_typ_id=1", con);
string companya_credit_amount = null, comapnyb_credit_amount = null;
con.Open();
SqlDataReader drc = cmd
c.ExecuteReader();
if (drc.HasRows)
{
while (drc.Read())
{
companya_credit_amount = drcp.IsDBNull(0)?string.Empty:Convert.ToString(drcp[0]);
}
drc.Close();
con.Close();
}
SqlCommand cmdcp = new SqlCommand("SELECT SUM(Credited_amount) FROM IMS_Credit_Dir WHERE Credit_comp_id=2 AND Crdt_typ_id=1", con);
con.Open();
SqlDataReader drcp = cmdcp.ExecuteReader();
if (drcp.HasRows)
{
while (drcp.Read())
{
companyb_credit_amount = drcp.IsDBNull(0)?string.Empty:Convert.ToString(drcp[0]);
}
drcp.Close();
con.Close();
}
if (!Page.IsPostBack)
{
int companyA = 0,companyB=0;
if (companya_credit_amount != "") { companyA = Convert.ToInt32(credit_amount.ToString()); }
if (companyb_credit_amount != ""){ companyB = Convert.ToInt32(companyb_credit_amount); }
int total = (companyA+companyB);
count_total_lbl.Text = "Rs." + " " + total.ToString();
count_comapnya_lbl.Text = "Rs." + " " + companya_credit_amount.ToString();
count_companyb_lbl.Text ="Rs."+" "+ companyb_credit_amount.ToString();
}
}
catch(Exception ex) { Label2.Text = ex.ToString(); }

C# how to check if database is not busy?

My class has a couple of methods going on. The first one is creating a database, that's done. Then, creates stored procedures that is being read from a sql file. then detach that DB. Now it seems that my store procedure query is taking a while to finish and my method to detach is being invoked while the database is busy. So how do I tell if the database is idle. The exception goes "cannot detach the database because it is currently in use"
Methods:
void CreateStoredProcedures(string type)
{
string spLocation = File.ReadAllText("CreateStoredProcedures.sql");
var conn = new SqlConnection(connectionString + ";database=" + type + DateTime.Now.ToString("yyyyMMdd"));
try
{
Server server = new Server(new ServerConnection(conn));
server.ConnectionContext.ExecuteNonQuery(spLocation);
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
}
bool DetachBackup(string type)
{
var conn = new SqlConnection(connectionString);
SqlCommand command = new SqlCommand("", conn);
command.CommandText = #"sys.sp_detach_db '" + type + DateTime.Now.ToString("yyyyMMdd") + "'";
try
{
conn.Open();
command.ExecuteNonQuery();
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
return false;
}
finally
{
if ((conn.State == ConnectionState.Open))
{
conn.Close();
}
}
return true;
}
Click event:
private void btnFullBackup_Click(object sender, EventArgs e)
{
lblStatus.Text = "Starting full backup...";
Execute("FULL");
progressBar.Value = 20;
lblStatus.Text = "Copying tables...";
progressBar.Value = 60;
CopyTables("FULL");
progressBar.Value = 70;
lblStatus.Text = "Creating stored procedures...";
CreateStoredProcedures("FULL");
progressBar.Value = 80;
CheckDBSize(newBackupLocation, "FULL");
progressBar.Value = 100;
MessageBox.Show("Backup was created successfully", "",
MessageBoxButtons.OK, MessageBoxIcon.Information);
lblStatus.Text = "Done";
progressBar.Value = 0;
if (DetachBackup("FULL") == false)
{
DetachBackup("FULL");
}
}

Chances are it's getting hung on its own connection. sp_detach_db's MSDN https://msdn.microsoft.com/en-CA/library/ms188031.aspx has the following suggestion under the section Obtain Exclusive Access:
USE master;
ALTER DATABASE [DBName] SET SINGLE_USER;
You're DetachBackup method will have connect to master, run the ALTER and the sp_detach_db procedure.

You aren't closing the connection in your CreateStoredProcedures method. Put using statements in like I've shown here and it should fix the problem. (Brief using statement explanation from Microsoft.)
Try this code for your methods:
void CreateStoredProcedures(string type)
{
string spLocation = File.ReadAllText("CreateStoredProcedures.sql");
using (var conn = new SqlConnection(connectionString + ";database=" + type + DateTime.Now.ToString("yyyyMMdd")))
{
try
{
Server server = new Server(new ServerConnection(conn));
server.ConnectionContext.ExecuteNonQuery(spLocation);
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
} // End of using, connection will always close when you reach this point.
}
bool DetachBackup(string type)
{
using (var conn = new SqlConnection(connectionString))
{
SqlCommand command = new SqlCommand(#"sys.sp_detach_db '" + type + DateTime.Now.ToString("yyyyMMdd") + "'", conn);
try
{
conn.Open();
command.ExecuteNonQuery();
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
return false;
}
} // End of using, connection will always close when you reach this point.
return true;
}

You shouldn't think of it as the database being "busy", but the error message uses good verbage: in use. To find out if the database is currently in use, the most accurate way would be to find out if any sessions have any lock in the particular database, by querying sys.dm_tran_locks. Here is a helper function to return a bool whether or not the database is in use:
bool IsDatabaseInUse(string databaseName)
{
using (SqlConnection sqlConnection = new SqlConnection("... your connection string ..."))
using (SqlCommand sqlCmd = new SqlCommand())
{
sqlCmd.Connection = sqlConnection;
sqlCmd.CommandText =
#"select count(*)
from sys.dm_tran_locks
where resource_database_id = db_id(#database_name);";
sqlCmd.Parameters.Add(new SqlParameter("#database_name", SqlDbType.NVarChar, 128)
{
Value = databaseName
});
sqlConnection.Open();
int sessionCount = Convert.ToInt32(sqlCmd.ExecuteScalar());
if (sessionCount > 0)
return true;
else
return false;
}
}
Note: Make sure your initial catalog in your connection string isn't the database you're trying to make "not in use", as that'll put your current session in the context of the database, not allowing that operation to complete

Insert all data of a datagridview to database C#

I have a datagridview which is created by various action and user's manipulation of data. I want to insert all the data of the gridview to the database at once, I know I could try a code similar to this:
private void btnSaveProducts_Click(object sender, EventArgs e)
{
SqlConnection connection = DBConnectivity.getConnection();
if (connection != null)
{
try
{
for (int i = 0; i < dGvProducts.Rows.Count; i++)
{
string query = "INSERT INTO product (productName) " + "VALUES (#productName)";
SqlCommand command = DBConnectivity.getCommandForQuery(query, connection);
int result = command.ExecuteNonQuery();
Console.WriteLine(result + "");
}
// string query = "Insert into units(name,packing)values('" + txtNameUnit.Text + "' , '" + txtPackingUnit.Text + "')";
// SqlCommand command = DBConnectivity.getCommandForQuery(query, connection);
// int result = command.ExecuteNonQuery();
// Console.WriteLine(result + "");
}
catch (Exception ex)
{
}
finally
{
connection.Close();
}
}
}

As is, the code tries to execute a parameterized query but never assigns a value to the parameter. Even if you do, you never extract the cell values.
The code should look like this:
var query = "INSERT INTO product (productName) VALUES (#productName)";
using var(connection = DBConnectivity.getConnection())
using(var command = new SqlCommand(query, connection))
{
var productParam=command.Parameters.Add("#productName",SqlDbType.NVarChar,50);
connection.Open();
for (int i = 0; i < dGvProducts.Rows.Count; i++)
{
var productName=dGvProducts.Rows[i].Cells[somecolumn].Value;
productParam.Value=productName;
int result = command.ExecuteNonQuery();
Console.WriteLine(result);
}
}

Can any one tell whats' wrong in my transaction

Hi all i have written the following transaction to insert data but when i am getting an exception only the data which got the exception not inserting to db the remaining all are inserting
This is what i wrote
public bool addWhole(SqlTransaction osqlTrans)
{
m_flag = false;
osqlTrans = null;
SqlConnection osqlCon = new SqlConnection(constr);
if (osqlCon.State != ConnectionState.Open)
{
osqlCon.Open();
}
osqlTrans = osqlCon.BeginTransaction();
try
{
if (this.addRisk(osqlTrans, osqlCon))
{
if (this.addEconomical(osqlTrans, osqlCon))
{
osqlTrans.Commit();
}
}
}
catch (Exception ex)
{
osqlTrans.Rollback();
}
finally
{
osqlCon.Close();
}
return m_flag;
}
public bool addRisk(SqlTransaction oRiskTrans, SqlConnection oRiskConn)
{
con = new SqlConnection(constr);
if (con.State != ConnectionState.Open)
{
con.Open();
}
cmd = new SqlCommand("insert into tblEnrollmentData (EID,Eyear,Epercent) values('" + id + "','" + str + "','" + dbPercent + "')", con); //Even i tried adding transaction in command statement
if (cmd.ExecuteNonQuery() > 0)
{
m_flag = true;
}
}
public bool addEconomical(SqlTransaction oRiskTrans, SqlConnection oRiskConn)
{
con = new SqlConnection(constr);
if (con.State != ConnectionState.Open)
{
con.Open();
}
cmd = new SqlCommand("insert into tblEnrollmentData (EID,Eyear,Epercent) values('" + id + "','" + str + "','" + dbPercent + "')", con);//Even i tried adding transaction in command statement
if (cmd.ExecuteNonQuery() > 0)
{
m_flag = true;
}
}
I tried to rollback the transaction by failing the second condition but my first statement is inserting to DB.. What should i do in order to overcome this

I'm guessing its one of these things
1) You are not using the same connection object for all the different commands
2) You are not assigning the transaction to the commands before you execute them
3) Both perhaps
Try using the same connection object and assigning the transaction to the command before you execute it for an example see this page on MSDN. http://msdn.microsoft.com/en-us/library/86773566.aspx

Transaction is not shared between connections and you always create a new connection. Use oRiskConn specified as 2nd parameter of your methods.

As you are creating a new connection in every function your code didn't work. Just remove the connection
`con = new SqlConnection(constr);`
Replace it with the connection available in your function i.e
oRiskConn and don't initialize it as a new connection. If you did so again your transaction as per your requirement will not work. Also include oRiskTrans in your command object. Then it will works as per your requirement

I don't know what some of your parameters are but it looks like you want something like this:
class SomeClass
{
// These need to be set to appropriate values
int id, str;
double dbPercent;
string constr;
public bool addWhole()
{
var m_flag = false;
using (var osqlCon = new SqlConnection(constr))
{
if (osqlCon.State != ConnectionState.Open)
{
osqlCon.Open();
}
using (var osqlTrans = osqlCon.BeginTransaction())
{
try
{
if (m_flag = this.addRisk(osqlTrans))
{
if (m_flag = this.addEconomical(osqlTrans))
{
osqlTrans.Commit();
}
}
}
catch (Exception)
{
// Use $exception in watch window if you are debugging
osqlTrans.Rollback();
}
}
}
return m_flag;
}
public bool addRisk(SqlTransaction oRiskTrans)
{
var m_flag = false;
using (var cmd = new SqlCommand("insert into tblEnrollmentData (EID,Eyear,Epercent) values('" + id + "','" + str + "','" + dbPercent + "')"))
{
cmd.Transaction = oRiskTrans;
cmd.Connection = oRiskTrans.Connection;
if (cmd.ExecuteNonQuery() > 0)
{
m_flag = true;
}
}
return m_flag;
}
public bool addEconomical(SqlTransaction oRiskTrans)
{
var m_flag = false;
using (var cmd = new SqlCommand("insert into tblEnrollmentData (EID,Eyear,Epercent) values('" + id + "','" + str + "','" + dbPercent + "')"))
{
cmd.Transaction = oRiskTrans;
cmd.Connection = oRiskTrans.Connection;
if (cmd.ExecuteNonQuery() > 0)
{
m_flag = true;
}
}
return m_flag;
}
}