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How to Execute Parameterized SQL Statements: ADO.NET

As we know, SQL statements can be of simple type or may be parameterized. The parameterized query contains some parameters, which may be accepted through object of SqlParameter class. SqlParameter class is used to create the parameters used by the command object to execute the Sql queries.
Write the following code to select a record from the table groups which has a given name. The name is passed by the parameter i.e. Sql Parameter.
SqlConnection connection = new SqlConnection();
connection.ConnectionString = "Data Source= (LocalDb)\\v11.0; Initial Catalog=StockDb; Integrated Security=True";
SqlCommand command = new SqlCommand("select * from Groups where code=@code", connection);
command.Parameters.AddWithValue("@code", 04);
SqlDataReader dr = command.ExecuteReader();

Look out the command object which have a variable name @code. It is the syntax of parameter used. In the next line, the parameter is added by using the function AddWithValue(). This method takes two parameter i.e. one for variable name (same as used in command object) and the second one is its value.

Now when we execute this code, a single record having code = 04 will be returned and can be accessed by data reader object dr.

We can check the rows as the same procedure as in previous post.


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Memory representation of Linked List

             In memory the linked list is stored in scattered cells (locations).The memory for each node is allocated dynamically means as and when required. So the Linked List can increase as per the user wish and the size is not fixed, it can vary.

               Suppose first node of linked list is allocated with an address 1008. Its graphical representation looks like the figure shown below:

      Suppose next node is allocated at an address 506, so the list becomes,

  Suppose next node is allocated with an address with an address 10,s the list become,

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 In the above representation the data stored in the linked list is “INDIA”, the information part of each node contains one character. The external pointer root points to first node’s address 1005. The link part of the node containing information I contains 1007, the address of next node. The last node …