How to setup Models?

[allspiritseve]

It is not impossible to have models represented by joins, even in moderately complex systems. But if such models are needed on a regular basis they're much better represented in the DB itself using a view, which can be easily accessed as a standard table.

Does this 'database view' have to actually be located in the database, or could I maybe create a view class that works like a table data gateway, except instead of accessing a table, it accesses a specific group of tables? Or is there some reason why that wouldn't work?

vbmenu_register("postmenu_3607535", true);Query functions return results (as resource). If you convert them into arrays, you need to traverse this raw array for the second time to get formatted output.


IMHO is better pass directly results, although you have to write formatting objects for each type of db separately.

I have data that takes two queries to compile. Can I save both of these resources and access each without affecting the other?

[BerislavLopac]

Does this 'database view' have to actually be located in the database, or could I maybe create a view class that works like a table data gateway, except instead of accessing a table, it accesses a specific group of tables? Or is there some reason why that wouldn't work?

The whole idea of the view is to keep the data in the database. View (in this sense) is a relational DB concept, defined in the RDB theory -- see http://en.wikipedia.org/wiki/View_%28database%29

[allspiritseve]

The whole idea of the view is to keep the data in the database. View (in this sense) is a relational DB concept, defined in the RDB theory -- see http://en.wikipedia.org/wiki/View_%28database%29

Ok, if I create a view in my database, will that allow me full CRUD operations on the view, or is it a read-only kind of thing?

[BerislavLopac]

Read the Wikipedia link. It depends on the database you use.

[Cups]

On views and mysql 5.1, new information for me.

30.6.6: Can you insert into views that are based on joins?

It is possible, provided that your INSERT statement has a column list that makes it clear there's only one table involved.

You cannot insert into multiple tables with a single insert on a view.
http://dev.mysql.com/doc/refman/5.1/en/faqs-views.html

Have I understood this correctly, if your view is made up from a join, lets say its made up from people.name and balance.current, if you update balance.current in the view, that will in turn update the static table?

[blueyon]

Forget about views and trigger functions unless you are accessing the same database with multiple applications.

[kyberfabrikken]

Have I understood this correctly, if your view is made up from a join, lets say its made up from people.name and balance.current, if you update balance.current in the view, that will in turn update the static table?

Yes, but with some limitations. Basically, if the view is just a couple of joined tables, it will work fine; Just like you can update to a joined query.

I should warn though, that MySql's support for views is rather limited. They work, but in some cases, they are very inefficient.

Forget about views and trigger functions unless you are accessing the same database with multiple applications.

I don't think it's right to say that views are only useful for applications, with multiple frontends. Views are an abstraction, and as such quite a useful tool. If you have a large database, with properly normalised data, you'd often end up joining dozens of tables for your queries. Views help making this more manageable. Views can also be used for decoupling dependencies within the database. For example, a rule could be that tables are divided into logical groups (modules). Each module can internally use tables, but if a module uses tables from another module, it must go through that modules views. This is akin to protected/public properties in objects.