SQL query from C#

Question

I am trying to query SQL Server database from C#

I have class

Class_A 
{
  public fetch((string name, string last_name))
  {
    SqlConnection conn          


        

Answer 1

Try

select * from table where NAME = 'name' and LAST_NAME = 'last_name'

instead of

select * from table where NAME = name and LAST_NAME = last_name

Edit:

If name and last_name are your parameters then try this:

SqlCommand myCommand = new SqlCommand("select * from table where NAME = @name and LAST_NAME = @last_name", conn); 
myCommand.Parameters.AddWithValue( "@name", name );
myCommand.Parameters.AddWithValue( "@last_name", last_name );

Using parameterized commands means that you are invulnerable to a potential huge security hole - sql injection which is possible when command text is manually concatenated.