~~ॐ त्र्यम्बकम यजामहे सुगंधिम पुष्टि वर्धनम
उर्वा रुकमिव बन्धनात मृत्योर्मोक्षी यमामृतात~~
Meaning:
OM. We worship and adore you, O three-eyed one, O Shiva. You are sweet gladness, the fragrance of life, who nourishes us, restores our health, and causes us to thrive. As, in due time, the stem of the cucumber weakens, and the gourd if freed from the vine, so free us from attachment and death, and do not withhold immortality.
Tuesday, July 8, 2008
What is Gayatri Mantra?
What is Gayatri Mantra?
ॐ भूर्भुवः स्वः तत्सवितुर्वरेण्यँ भर्गो देवस्य धीमहि धियो यो न: प्रचोदयात्
O God, Thou art the Giver of Life, the Remover of pains and sorrows, the Bestower of happiness O Creator of the Universe, may we receive Thy Supreme Sin destroying light, May Thou guide our intellect in the right direction.
In short it is a prayer to the Almighty Supreme God, the Creator of entire cosmos, the essence of our life existence, who removes all our sins, pains and sufferings and grants happiness; beseeching His divine grace to inculcate within us His Divinity and Brilliance, which may purify us and guide our wisdom on the righteous path.
Is not this mantra specific to Hindu religion?
This mantra is very generic and diplomatic. It is a very generic prayer and no religion or ideology which is God centric will have any objection for this prayer.
Why this mantra is considered as the most important in Hindu mythology?
It is our thoughts which makes our destiny. As I have mentioned in my other articles that Vishnu lives inside everybody and He inspires us to do good or bad. He is like a child and gets affected with the surroundings and environment in which we are living. One of the name of Vishnu is Hari which means Monkey. Sometimes Vishnu also imitates as monkey. In this mantra we pray to God to purify our soul and asks the purest form of god to come and live inside us. We pray to God that this purest form of god inspires us to go good things.
This mantra purifies our thoughts and inspires us to do good and constructive things.
Wednesday, April 23, 2008
Working with Transactions in ADO.NET
A transaction is a group of operations combined into a logical unit of work that is either guaranteed to be executed as a whole or rolled back. Transactions help the database in satisfying all the ACID (Atomic, Consistent, Isolated, and Durable). Transaction processing is an indispensible part of ADO.NET. It guarantees that a block of statements will either be executed in its entirety or rolled back,( i.e., none of the statements will be executed). Transaction processing has improved a lot in ADO.NET 2.0. This article discusses how we can work with transactions in both ADO.NET 1.1 and 2.0 versions.
Implementing Transactions in ADO.NET
Note that in ADO.NET, the transactions are started by calling the BeginTransaction method of the connection class. This method returns an object of type SqlTransaction. Other ADO.NET connection classes like OleDbConnection, OracleConnection also have similar methods. Once you are done executing the necessary statements within the transaction unit/block, make a call to the Commit method of the given SqlTransaction object, or you can roll back the transaction using the Rollback method, depending on your requirements (if any error occurs when the transaction unit/block was executed).
To work with transactions in ADO.NET, you require an open connection instance and a transaction instance. Then you need to invoke the necessary methods as stated later in this article. Transactions are supported in ADO.NET by the SqlTransaction class that belongs to the System.Data.SqlClient namespace.
The two main properties of this class are as follows:
Connection: This indicates the SqlConnection instance that the transaction instance is associated with
IsolationLevel: This specifies the IsolationLevel of the transaction
The following are the methods of this class that are noteworthy:
Commit() This method is called to commit the transaction
Rollback() This method can be invoked to roll back a transaction. Note that a transaction can only be rolled back after it has been committed.
Save() This method creates a save point in the transaction. This save point can be used to rollback a portion of the transaction at a later point in time. The following are the steps to implement transaction processing in ADO.NET.
Connect to the database
Create a SqlCommand instance with the necessary parameters
Open the database connection using the connection instance
Call the BeginTransaction method of the Connection object to mark the beginning of the transaction
Execute the sql statements using the command instance
Call the Commit method of the Transaction object to complete the
transaction, or the Rollback method to cancel or abort the transaction
Close the connection to the database
The following code snippet shows how we can implement transaction processing using ADO.NET in our applications.
string connectionString = ...; //Some connection string
SqlConnection sqlConnection = new SqlConnection(connectionString);
sqlConnection.Open();
SqlTransaction sqlTransaction = sqlConnection.BeginTransaction();
SqlCommand sqlCommand = new SqlCommand();
sqlCommand.Transaction = sqlTransaction;
try
{
sqlCommand.CommandText = "Insert into Employee (EmpCode, EmpName) VALUES (1, 'Joydip')";
sqlCommand.ExecuteNonQuery();
sqlCommand.CommandText = "Insert into Dept (DeptCode, DeptName, EmpCode) VALUES (9, 'Software', 1)";
sqlCommand.ExecuteNonQuery();
sqlTransaction.Commit();
//Usual code
}
catch(Exception e)
{
sqlTransaction.Rollback();
//Usual code
}
finally
{
sqlConnection.Close();
}
The next piece of code illustrates how we can use the “using” statement for the above code. According to MSDN, the "using" statement, "defines a scope, outside of which an object or objects will be disposed. A using statement can be exited either when the end of the using statement is reached or if an exception is thrown and control leaves the statement block before the end of the statement".
using (SqlConnection sqlConnection = new SqlConnection(connectionString))
{
SqlCommand command = connection.CreateCommand();
SqlTransaction transaction = null;
try
{
sqlConnection.Open();
transaction = sqlConnection.BeginTransaction();
command.Transaction = transaction;
command.CommandText = "Insert into employee (empID, empName) values (1, 'Joydip');
command.ExecuteNonQuery();
command.CommandText = "Insert into dept (deptID,deptName,empID) values (9,'Software',1)";
command.ExecuteNonQuery();
transaction.Commit();
}
catch(Exception ex)
{
transaction.Rollback();
throw ex;
}
finally
{
sqlConnection.Close();
}
}
The Microsoft's ADO.NET version 2.0 added a lot of new features to its earlier counterpart to add moer flexibility and ease of use. As far as transactions are concerned, a new namespace called System.Transactions has been introduced that promises a significantly improved support for distributed transactions. It contains a class called TransactionScope that can run a set of statements. It can also determine whether the objects in the scope have support for transactions. If the transaction has completed successfully, the changes are committed to the database else it is rolled back. We need to specify whether the transaction block is complete by making a call to the TransactionScope.Complete method explicitly, else, the transaction would be rolled back when the transaction instance would be discarded by the implicit Dispose method.
The following piece of code illustrates what we have learnt so far in this section.
bool IsConsistent = false;
using (System.Transactions.TransactionScope transactionScope = new System.Transactions.TransactionScope())
{
SqlConnection sqlConnection = newSqlConnection(connectionString);
string sqlString = "Update emp set empName = 'Joydip Kanjilal' where empID = 9";
SqlCommand cmd1 = newSqlCommand(sql, cn);
sqlConnection.Open();
cmd1.ExecuteNonQuery();
sqlConnection.Close();
transactionScope.Consistent = IsConsistent;
}
TransactionScope also has support for distributed transactions. We can implement transactions for multiple database connections using it. The following piece of code shows how we can implement transactional support for multiple databases using the TransactionScope class.
using (TransactionScope transactionScope = new TransactionScope())
{
using (SqlConnection codesDatabaseConnection = new SqlConnection(codesDatabaseConnectionString))
{
SqlCommand sqlCommandCodes = codesDatabaseConnection.CreateCommand();
sqlCommandCodes.CommandText = "Insert Into codes (codeID,codeText) values (1,'Test')";
codesDatabaseConnection.Open();
sqlCommandCodes.ExecuteNonQuery();
codesDatabaseConnection.Close();
}
using (SqlConnection statesDatabaseConnection = new SqlConnection(statesDatabaseConnectionString))
{
SqlCommand sqlCommandStates = statesDatabaseConnection.CreateCommand();
sqlCommandStates.CommandText = "Insert into States(stateID,stateName) values (1, 'Test')";
codesDatabaseConnection.Open();
sqlCommandStates.ExecuteNonQuery();
statesDatabaseConnection.Close();
}
transactionScope.Complete();
}
Points to be noted
It should be noted that the SqlTransaction object returned by the BeginTransaction () method has to be assigned to the Transaction property of the Command object; else an InvalidOperationException will be thrown by the application when the first query is executed. Likewise, the Connection instance should be open by invoking the Open method on it prior to starting a new transaction; else an InvalidOperationException would be thrown. In order to improve the performance of applications, we should try to keep the transactions (the transaction units/blocks that contain the statements to be executed in a batch as a whole) as short as possible. This will help minimize the lock contention and hence increase throughput. Further, we should analyze whether or not we actually require a transaction for a batch of statements. Try not to unnecessarily have transactional statements in you code as it might have a performance drawback due to the reasons stated above
Implementing Transactions in ADO.NET
Note that in ADO.NET, the transactions are started by calling the BeginTransaction method of the connection class. This method returns an object of type SqlTransaction. Other ADO.NET connection classes like OleDbConnection, OracleConnection also have similar methods. Once you are done executing the necessary statements within the transaction unit/block, make a call to the Commit method of the given SqlTransaction object, or you can roll back the transaction using the Rollback method, depending on your requirements (if any error occurs when the transaction unit/block was executed).
To work with transactions in ADO.NET, you require an open connection instance and a transaction instance. Then you need to invoke the necessary methods as stated later in this article. Transactions are supported in ADO.NET by the SqlTransaction class that belongs to the System.Data.SqlClient namespace.
The two main properties of this class are as follows:
Connection: This indicates the SqlConnection instance that the transaction instance is associated with
IsolationLevel: This specifies the IsolationLevel of the transaction
The following are the methods of this class that are noteworthy:
Commit() This method is called to commit the transaction
Rollback() This method can be invoked to roll back a transaction. Note that a transaction can only be rolled back after it has been committed.
Save() This method creates a save point in the transaction. This save point can be used to rollback a portion of the transaction at a later point in time. The following are the steps to implement transaction processing in ADO.NET.
Connect to the database
Create a SqlCommand instance with the necessary parameters
Open the database connection using the connection instance
Call the BeginTransaction method of the Connection object to mark the beginning of the transaction
Execute the sql statements using the command instance
Call the Commit method of the Transaction object to complete the
transaction, or the Rollback method to cancel or abort the transaction
Close the connection to the database
The following code snippet shows how we can implement transaction processing using ADO.NET in our applications.
string connectionString = ...; //Some connection string
SqlConnection sqlConnection = new SqlConnection(connectionString);
sqlConnection.Open();
SqlTransaction sqlTransaction = sqlConnection.BeginTransaction();
SqlCommand sqlCommand = new SqlCommand();
sqlCommand.Transaction = sqlTransaction;
try
{
sqlCommand.CommandText = "Insert into Employee (EmpCode, EmpName) VALUES (1, 'Joydip')";
sqlCommand.ExecuteNonQuery();
sqlCommand.CommandText = "Insert into Dept (DeptCode, DeptName, EmpCode) VALUES (9, 'Software', 1)";
sqlCommand.ExecuteNonQuery();
sqlTransaction.Commit();
//Usual code
}
catch(Exception e)
{
sqlTransaction.Rollback();
//Usual code
}
finally
{
sqlConnection.Close();
}
The next piece of code illustrates how we can use the “using” statement for the above code. According to MSDN, the "using" statement, "defines a scope, outside of which an object or objects will be disposed. A using statement can be exited either when the end of the using statement is reached or if an exception is thrown and control leaves the statement block before the end of the statement".
using (SqlConnection sqlConnection = new SqlConnection(connectionString))
{
SqlCommand command = connection.CreateCommand();
SqlTransaction transaction = null;
try
{
sqlConnection.Open();
transaction = sqlConnection.BeginTransaction();
command.Transaction = transaction;
command.CommandText = "Insert into employee (empID, empName) values (1, 'Joydip');
command.ExecuteNonQuery();
command.CommandText = "Insert into dept (deptID,deptName,empID) values (9,'Software',1)";
command.ExecuteNonQuery();
transaction.Commit();
}
catch(Exception ex)
{
transaction.Rollback();
throw ex;
}
finally
{
sqlConnection.Close();
}
}
The Microsoft's ADO.NET version 2.0 added a lot of new features to its earlier counterpart to add moer flexibility and ease of use. As far as transactions are concerned, a new namespace called System.Transactions has been introduced that promises a significantly improved support for distributed transactions. It contains a class called TransactionScope that can run a set of statements. It can also determine whether the objects in the scope have support for transactions. If the transaction has completed successfully, the changes are committed to the database else it is rolled back. We need to specify whether the transaction block is complete by making a call to the TransactionScope.Complete method explicitly, else, the transaction would be rolled back when the transaction instance would be discarded by the implicit Dispose method.
The following piece of code illustrates what we have learnt so far in this section.
bool IsConsistent = false;
using (System.Transactions.TransactionScope transactionScope = new System.Transactions.TransactionScope())
{
SqlConnection sqlConnection = newSqlConnection(connectionString);
string sqlString = "Update emp set empName = 'Joydip Kanjilal' where empID = 9";
SqlCommand cmd1 = newSqlCommand(sql, cn);
sqlConnection.Open();
cmd1.ExecuteNonQuery();
sqlConnection.Close();
transactionScope.Consistent = IsConsistent;
}
TransactionScope also has support for distributed transactions. We can implement transactions for multiple database connections using it. The following piece of code shows how we can implement transactional support for multiple databases using the TransactionScope class.
using (TransactionScope transactionScope = new TransactionScope())
{
using (SqlConnection codesDatabaseConnection = new SqlConnection(codesDatabaseConnectionString))
{
SqlCommand sqlCommandCodes = codesDatabaseConnection.CreateCommand();
sqlCommandCodes.CommandText = "Insert Into codes (codeID,codeText) values (1,'Test')";
codesDatabaseConnection.Open();
sqlCommandCodes.ExecuteNonQuery();
codesDatabaseConnection.Close();
}
using (SqlConnection statesDatabaseConnection = new SqlConnection(statesDatabaseConnectionString))
{
SqlCommand sqlCommandStates = statesDatabaseConnection.CreateCommand();
sqlCommandStates.CommandText = "Insert into States(stateID,stateName) values (1, 'Test')";
codesDatabaseConnection.Open();
sqlCommandStates.ExecuteNonQuery();
statesDatabaseConnection.Close();
}
transactionScope.Complete();
}
Points to be noted
It should be noted that the SqlTransaction object returned by the BeginTransaction () method has to be assigned to the Transaction property of the Command object; else an InvalidOperationException will be thrown by the application when the first query is executed. Likewise, the Connection instance should be open by invoking the Open method on it prior to starting a new transaction; else an InvalidOperationException would be thrown. In order to improve the performance of applications, we should try to keep the transactions (the transaction units/blocks that contain the statements to be executed in a batch as a whole) as short as possible. This will help minimize the lock contention and hence increase throughput. Further, we should analyze whether or not we actually require a transaction for a batch of statements. Try not to unnecessarily have transactional statements in you code as it might have a performance drawback due to the reasons stated above
Thursday, March 27, 2008
Ways for online privacy....
REUTERS - Here are 10 ways to keep personal information secure when online:
1) Favour common sense over technological solutions. Keep personal documents safe, preferably in a locked drawer. Shred bank statements, credit card slips and bills before throwing them away.
2) If it's too good to be true, it is. Never open unsolicited "spam" messages. Delete e-mails offering cash, free gifts or stock tips. Millions of unsolicited "spam" messages are sent every day in an attempt to defraud computer users.
3) Basic prevention helps. Protect your computer against identity theft. Install security software to combat viruses, spyware and spam and keep it updated.
4) Know enough about your firewall, the barrier between the public Internet and a personal computer, to know when it is working and when it isn't. Don't worry about the geeky complexity of it all, just know it's operating.
5) Beware of "phishing", where criminals trick people into revealing personal or financial details, often by sending e-mails purporting to be from a bank. Never casually reply to requests for your personal financial details.
6) Keep your private e-mail address secure. Consider using different e-mail accounts for shopping, banking, friends and work. There are many free account providers.
7) Do not use the same password for different sites. Choose passwords with a mix of letters, numbers and symbols. Don't use obvious passwords, such as your first name or "123456" and don't write them down. For memory's sake, choosing a basic root word, then rotating numbers, is safer.
8) Make online payments safely. Never enter a card number unless there is a padlock in the Web browser's frame, rather than the Web page. The Web address should begin with "https" -- the extra "S" stands for "secure". Consider reserving one credit card for Web use or signing up for a separate online payment service like PayPal.
9) Secure your wireless network at home and be wary when using public access points. Encrypt the connection to scramble communications over the network. Turn off the wireless network when you're not using it.
10) Treat your laptop computer like cash -- never leave it in a locked car or turn your back while using it in a public place. The same holds true with your mobile phone: Lock your phone (and any passwords you keep on it) when not using it.
For more on privacy, see http://uk.reuters.com/news/globalcoverage/onlinePrivacy
(Sources: Britain's Home Office (interior ministry); Get Safe Online, a government-backed British Internet security advice Web site; OnGuardOnline.gov, a site run by the U.S. Federal Trade Commission; www.diyonlinesecurity.co.uk)
10 Commandments for Success..!!
Here are ten points gleaned from the writings of Sri Swami Sivananda, which can lead any individual towards success in their chosen path in life. These guidelines have the power to benefit you - physically, mentally and spiritually.
1. Have a simple and unassuming manner of life.
2. Live not to eat, but eat to live.
3. Bear no envy. Commit no slander. Speak no falsehood. Practise no deceit. Harbor no malice. You will be ever joyful, happy and peaceful.
4. Righteousness is the rule of life. Lead a virtuous life. Strictly adhere to Dharma. Human life is not human without virtues. Study the lives of saints and draw inspiration from them.
5. Cultivate a melting heart, the giving hand, the kindly speech, the life of service, equal vision, and impartial attitude.
Your life will, indeed, be blessed.
6. Lead a regulated life. Take hold of each day as if it were the last day, and utilize every second in prayer, meditation and service. Let your life become a continuous sacrifice to God.
7. Live in the present. Forget the past. Give up hopes of the future.
8. Understand well the meaning of life, and then start the quest.
9. Life is thy greatest gift. Utilize every second profitably.
10. Success often comes to those who dare and act. It seldom comes to the timid.
May you all attain success in life!
- Swami Sivananda--
1. Have a simple and unassuming manner of life.
2. Live not to eat, but eat to live.
3. Bear no envy. Commit no slander. Speak no falsehood. Practise no deceit. Harbor no malice. You will be ever joyful, happy and peaceful.
4. Righteousness is the rule of life. Lead a virtuous life. Strictly adhere to Dharma. Human life is not human without virtues. Study the lives of saints and draw inspiration from them.
5. Cultivate a melting heart, the giving hand, the kindly speech, the life of service, equal vision, and impartial attitude.
Your life will, indeed, be blessed.
6. Lead a regulated life. Take hold of each day as if it were the last day, and utilize every second in prayer, meditation and service. Let your life become a continuous sacrifice to God.
7. Live in the present. Forget the past. Give up hopes of the future.
8. Understand well the meaning of life, and then start the quest.
9. Life is thy greatest gift. Utilize every second profitably.
10. Success often comes to those who dare and act. It seldom comes to the timid.
May you all attain success in life!
- Swami Sivananda--
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