List<BankNameSpace__Obj1__c> obj=[Select BankNameSpace__BSELookup__r.Name,Name from BankNameSpace__Obj1__c];
SELECT Id, Name, Account.Name
FROM Contact
Parent to child
List<BankNameSpace__BSE__c> obj1=[Select BankNameSpace__BSE__c.Name,(Select Name from BankNameSpace__BSE__c.BankNameSpace__Obj1__r) from BankNameSpace__BSE__c];
SELECT Name,
(
SELECT LastName
FROM Contacts
)
FROM Account
http://www.salesforce.com/us/developer/docs/soql_sosl/Content/sforce_api_calls_soql_relationships.htm
Child to parent:
Parent to child
let me know if you have any queries.
thanks,
Ramesh