Going Twice to the DB vs Join- In Order To Get Siblings

Question

User933695886 posted

Hi,

I have a simple parent and child entitis: Country, City. City has Country_Id and City_Id.

I need to write a DAL method that recives a City_Id as a parameter, and manipulates the given city and some other cities in the country.

My DAL is ADO.NET to a DATASET class generated by the Visual Studio 2008.

What would be a better practice:

1. Going twice to the DB: Using SqlDataReader to retrieve the Country_Id and then SqlDataAdapter to fill my DataTable?
2. Going once to the DB: Using SqlDataAdapter to bring the right cities by join self Cities table on Country_Id?
3. Another way?

TIA