SQL RDBMS : one query or multiple calls
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After looking around the internet, I decided to create DAOs that returned objects (POJOs) to the calling business logic function/method.
For example: a Customer object with a Address reference would be split in the RDBMS into two tables; Customer and ADDRESS. The CustomerDAO would be in charge of joining the data from the two tables and create both an Address POJO and Customer POJO adding the address to the customer object. Finally return the fulll Customer POJO.
Simple, however, now i am at a point where i need to join three or four tables and each representing an attribute or list of attributes for the resulting POJO. The sql will include a group by but i will still result with multiple rows for the same pojo, because some of the tables are joining a one to many relationship. My app code will now have to loop through all the rows trying to figure out if the rows are the same with different attributes or if the record should be a new POJO.
Should I continue to create my daos using this technique or break up my Pojo creation into multiple db calls to make the code easier to understand and maintain?
