RE: [PHP] Re: Newbie: Composition by Association - Pagination Class general question.

> As for (1) even in my pre-OO days I was used to using a single generic > DAO > for all database access. The only time that more than one DAO existed > was > for a different DBMS engine. This is why I have one DAO class for MySQL, > one > for PostgreSQL and another for Oracle. If you are incapable of writing > a > single generic DAO then it just shows that you still have a lot to > learn. > For an idea on how this works take a look at > http://www.tonymarston.net/php-mysql/databaseobjects.html I'm absolutly sure that I have a lot to learn. Really a lot. :-) I have post some days ago, a way for using a generic CRUD class and DAO, but I get no replys so I wrongly suppose that my question was a nonsense question, and that CRUD and DAO would be a nonsense. > As for (2) it should be obvious that pagination is not an entity in its > own > right that has its own properties and methods, it is merely a function > which > can be performed on any entity within the system. Ok... > It should also be > obvious > that the requirements of pagination cannot be satisfied in a single > class as > some of the processing has to be handled in the presentation (UI) layer > while the remainder is handled in the data access layer. That's why I was thinking on using a Decorator Object on the Pagination Class (that will retrieve DAO values to operate). > The > presentation > layer needs a means to submit a request for a particular page number as > well > as the page size (rows per page). These two values are sent to the DAO > which > then translates them into values for LIMIT and OFFSET. After the DAO > has > issued the sql SELECT statement it needs to return two values - the > current > page number and the last available page number. The presentation layer > then > needs a mechanism to display these two values. This is explained in > http://www.tonymarston.net/php-mysql/pagination.html Thanks for explain the workflow! I will read. > > If you still don't see how this works then you can run my sample > application > at http://www.tonymarston.net/php-mysql/sample-application.html > You can > even > download the code so that you can step through it with your debugger. I haven't learn how to use a debugger yet. And I'm sure it would help me a lot on understanding some data workflow... Thanks, Márcio