/*
* C# Programmers Pocket Consultant
* Author: Gregory S. MacBeth
* Email: gmacbeth@comporium.net
* Create Date: June 27, 2003
* Last Modified Date:
* Version: 1
*/
using System;
using System.Data;
using System.Data.SqlClient;
namespace Client.Chapter_13___ADO.NET
{
public class UpdatingDataUsingTransactions
{
static void Main(string[] args)
{
SqlConnection MyConnection = new SqlConnection(@"Data Source=(local); Initial Catalog = CaseManager; Integrated Security=true");
MyConnection.Open();
String MyString = "INSERT INTO Test(ID, Contact, Email)VALUES(1, 'Greg', 'Mac')";
SqlTransaction MyTransaction = MyConnection.BeginTransaction();
SqlCommand MyCmd = new SqlCommand(MyString, MyConnection, MyTransaction);
MyCmd.ExecuteScalar();
MyTransaction.Commit();
MyConnection.Close();
}
}
}
Database ADO.net
Commit two delete sql command
using System;
using System.Data;
using System.Data.SqlClient;
class SqlDemo {
static void Main(){
string connString = "server=(local)SQLEXPRESS;database=MyDatabase;Integrated Security=SSPI";
SqlConnection cn = new SqlConnection(connString);
cn.Open();
SqlTransaction objTrans = cn.BeginTransaction();
try{
SqlCommand cmd = cn.CreateCommand();
cmd.CommandType = CommandType.Text;
cmd.Transaction = objTrans;
cmd.CommandText = "DELETE Employee WHERE Id = 222";
cmd.ExecuteNonQuery();
cmd.CommandText="DELETE Employee WHERE Id = 333";
cmd.ExecuteNonQuery();
objTrans.Commit();
Console.WriteLine("Transaction Committed
");
}
catch (System.Data.SqlClient.SqlException ex)
{
objTrans.Rollback();
Console.WriteLine("Error - TRANSACTION ROLLED BACK
" + ex.Message);
}
catch (System.Exception ex)
{
Console.WriteLine("System Error
" + ex.Message);
}
finally
{
cn.Close();
}
}
}
Transaction roll back and commit
using System;
using System.Data;
using System.Data.SqlClient;
class SqlDemo {
static void Main(){
string connString = "server=(local)SQLEXPRESS;database=MyDatabase;Integrated Security=SSPI";
SqlConnection cn = new SqlConnection(connString);
cn.Open();
SqlTransaction objTrans = cn.BeginTransaction();
try
{
SqlCommand cmd = cn.CreateCommand();
cmd.CommandType = CommandType.Text;
cmd.Transaction = objTrans;
cmd.CommandText = "DELETE Employee WHERE Id = 222";
cmd.ExecuteNonQuery();
objTrans.Commit();
Console.WriteLine("Transaction Committed
" );
}
catch (System.Data.SqlClient.SqlException ex)
{
objTrans.Rollback();
Console.WriteLine("Error - TRANSACTION ROLLED BACK
" + ex.Message);
}
catch (System.Exception ex)
{
Console.WriteLine("System Error
" + ex.Message);
}
finally
{
cn.Close();
}
}
}
illustrates the use of transactions
/*
Mastering Visual C# .NET
by Jason Price, Mike Gunderloy
Publisher: Sybex;
ISBN: 0782129110
*/
/*
Example23_4.cs illustrates the use of transactions
*/
using System;
using System.Data;
using System.Data.SqlClient;
public class Example23_4
{
public static void Main()
{
// formulate a string containing the details of the
// database connection
string connectionString =
"server=localhost;database=Northwind;uid=sa;pwd=sa";
// create a SqlConnection object to connect to the
// database, passing the connection string to the constructor
SqlConnection mySqlConnection =
new SqlConnection(connectionString);
// open the database connection using the
// Open() method of the SqlConnection object
mySqlConnection.Open();
// step 1: create a SqlTransaction object and start the transaction
// by calling the BeginTransaction() method of the SqlConnection
// object
SqlTransaction mySqlTransaction =
mySqlConnection.BeginTransaction();
// step 2: create a SqlCommand object to hold a SQL statement
SqlCommand mySqlCommand = mySqlConnection.CreateCommand();
// step 3: set the Transaction property for the SqlCommand object
mySqlCommand.Transaction = mySqlTransaction;
// step 4: formulate a string containing the first INSERT statement
string insertString =
"INSERT INTO Customers (" +
" CustomerID, CompanyName, ContactName, Address" +
") VALUES (" +
" 'T2COM', 'T2 Company', 'Jason Price', '1 Main Street'" +
")";
// step 5: set the CommandText property of the SqlCommand object to
// the INSERT string
mySqlCommand.CommandText = insertString;
// step 6: run the first INSERT statement
Console.WriteLine("Running first INSERT statement");
mySqlCommand.ExecuteNonQuery();
// step 7: formulate a second INSERT statement
insertString =
"INSERT INTO Orders (" +
" CustomerID" +
") VALUES (" +
" 'T2COM'" +
")";
// step 8: set the CommandText property of the SqlCommand object to
// the second INSERT string
mySqlCommand.CommandText = insertString;
// step 9: run the second INSERT statement
Console.WriteLine("Running second INSERT statement");
mySqlCommand.ExecuteNonQuery();
// step 10: commit the transaction using the Commit() method
// of the SqlTransaction object
Console.WriteLine("Committing transaction");
mySqlTransaction.Commit();
// close the database connection using the Close() method
// of the SqlConnection object
mySqlConnection.Close();
}
}
Use of a transaction
using System;
using System.Data;
using System.Data.SqlClient;
class ExecuteTransaction
{
public static void Main()
{
SqlConnection mySqlConnection =new SqlConnection("server=(local)SQLEXPRESS;database=MyDatabase;Integrated Security=SSPI;");
mySqlConnection.Open();
SqlTransaction mySqlTransaction = mySqlConnection.BeginTransaction();
SqlCommand mySqlCommand = mySqlConnection.CreateCommand();
mySqlCommand.Transaction = mySqlTransaction;
mySqlCommand.CommandText =
"INSERT INTO Employee (" +
" ID, FirstName" +
") VALUES (" +
" 10, 'Jason'" +
")";
Console.WriteLine("Running first INSERT statement");
mySqlCommand.ExecuteNonQuery();
mySqlCommand.CommandText =
"INSERT INTO Employee (" +
" ID, FirstName" +
") VALUES (" +
" 11, 'Jason'" +
")";
Console.WriteLine("Running second INSERT statement");
mySqlCommand.ExecuteNonQuery();
Console.WriteLine("Committing transaction");
mySqlTransaction.Commit();
mySqlConnection.Close();
}
}
Set a savepoint in a transaction
using System;
using System.Data;
using System.Data.SqlClient;
class Savepoint {
public static void Main() {
SqlConnection mySqlConnection =
new SqlConnection(
"server=localhost;database=Northwind;uid=sa;pwd=sa"
);
mySqlConnection.Open();
SqlTransaction mySqlTransaction = mySqlConnection.BeginTransaction();
SqlCommand mySqlCommand = mySqlConnection.CreateCommand();
mySqlCommand.Transaction = mySqlTransaction;
mySqlCommand.CommandText =
"INSERT INTO Customers ( " +
" CustomerID, CompanyName " +
") VALUES ( " +
" 'J8COM', 'J8 Company' " +
")";
int numberOfRows = mySqlCommand.ExecuteNonQuery();
Console.WriteLine("Number of rows inserted = " + numberOfRows);
mySqlTransaction.Save("SaveCustomer");
mySqlCommand.CommandText = "INSERT INTO Orders (CustomerID ) VALUES ( 'J8COM' )";
numberOfRows = mySqlCommand.ExecuteNonQuery();
Console.WriteLine("Number of rows inserted = " + numberOfRows);
mySqlTransaction.Rollback("SaveCustomer");
mySqlCommand.CommandText =
"SELECT CustomerID, CompanyName " +
"FROM Customers " +
"WHERE CustomerID = 'J8COM'";
SqlDataReader mySqlDataReader = mySqlCommand.ExecuteReader();
while (mySqlDataReader.Read()) {
Console.WriteLine("mySqlDataReader[" CustomerID"] = " +
mySqlDataReader["CustomerID"]);
Console.WriteLine("mySqlDataReader[" CompanyName"] = " +
mySqlDataReader["CompanyName"]);
}
mySqlDataReader.Close();
mySqlCommand.CommandText = "DELETE FROM Customers WHERE CustomerID = 'J8COM'";
numberOfRows = mySqlCommand.ExecuteNonQuery();
Console.WriteLine("Number of rows deleted = " + numberOfRows);
mySqlTransaction.Commit();
mySqlConnection.Close();
}
}
Get table Schema
using System;
using System.Data;
using System.Data.SqlClient;
class SchemaTable
{
static void Main(string[] args)
{
string connString = "server=(local)SQLEXPRESS;database=MyDatabase;Integrated Security=SSPI";
string sql = @"select * from employee";
SqlConnection conn = new SqlConnection(connString);
try {
conn.Open();
SqlCommand cmd = new SqlCommand(sql, conn);
SqlDataReader reader = cmd.ExecuteReader();
DataTable schema = reader.GetSchemaTable();
foreach (DataRow row in schema.Rows)
{
foreach (DataColumn col in schema.Columns){
Console.WriteLine(col.ColumnName + " = " + row[col]);
Console.WriteLine("Null value allowed: " + col.AllowDBNull);
}
}
reader.Close();
} catch(Exception e) {
Console.WriteLine("Error Occurred: " + e);
} finally {
conn.Close();
}
}
}