Question

If say I need to run two separate SQL statements against two separate databases. Right now I do (pseudocode):

Try{

declare variable connectionA to DatabaseA 
declare variable connectionB to DatabaseB 

connectionA.open()
connectionB.open() 


declare variable SQLCmdA with ConnectionA and one SQL statement 
declare variable SQLCmdB with ConnectionB and another SQL statement 

SQLCmdA.executeNonQuery() 
SQLCmdB.executeNonQuery()

}

Catch () 
{
   print error message
}

Finally(){ 
  connectionA.close() 
  connectionB.close()
  SQLCmdA.Dispose()
  SQLCmdB.Dispose() 
} 

The above seems very clumsy. And if I have three different sql statements, i would need three different SQLCmd variables.

Is there a “standard” way of doing such things, especially in terms of efficiency, performance? if anyone can provide a simple improved pseudocode, that’d be great.

In addition, do I need to worry about implementing Connection Pooling, to conserve resource and speed up the program? If so, how do I implement it in this case?

Thanks!

Answer 1

Instead of adding variables, why not make a class?

public class MyDatabaseConnection {
    public MyDatabaseConnection(string connectionString) {
        this.connectionString = connectionString;
        // create a database connection perhaps
    }
    // some methods for querying a database
    public void execute(string query) { }
}

In this case it’s easy to add a third database connection

MyDatabaseConnection con1 = new MyDatabaseConnection("Server=localhost");
MyDatabaseConnection con2 = new MyDatabaseConnection("Server=other_server");
MyDatabaseConnection con3 = new MyDatabaseConnection("Server=third_one");

And execute an sql query on each

MyDatabaseConnection[] cons = new MyDatabaseConnection[]{ con1, con2, con3 };
foreach (MyDatabaseConnection con in cons) {
    con.execute(someSqlCommandText);
}