More on V4RB 4.8.1 apps -- about Class Style ... more

[Steve Albin]

On Oct 15, 2013, at 1:40 PM, Ruslan Zasukhin wrote:

> On 10/11/13 11:20 PM, "Steve Albin" <steve at steve-albin.com> wrote:
> 
>> I should clarify that I am abandoning the class way for defining the database
>> tables.  I still create a subclass of VDatabase, but I don't create classes
>> for all the tables.  I find that if your VTable classes do not match your
>> database EXACTLY, then you can have problems.  Of course, this should be true
>> - they should match.  But, in practice I've found that database schemas easily
>> change.  Fields that had no default defined get a default NULL defined.
>> Fields that were not defined as indexed get indexed.  I suspect as Valentina
>> versions change, schemas get updated in subtle ways that may effect how the
>> VTable classes should be defined.
>> 
>> There is no need to use the VTable classes.  Valentina knows what the database
>> contains already.  I create subclasses of VCursor and do all my access of the
>> database via SQL.
>> 
>> My one application where I switched to not using classes for opening the
>> tables is much more stable.  I realize that I may have been using the table
>> classes incorrectly, but I'll take success however I find it.
> 
> May be future we will redesign this Class way ...
> Don't know yet how :-)
> 
> 
> From one side Class-way adds OO-style,
> Btw it not uses SQL at all, in contrast to ORMs around SQL-dbs,
> 
> 
> Also in contrast to ORM-styles:
>    they create instance of each tblPerson record ..
>    we in Class-way have only single - current record
> 
> May be we need somehow take best of both ways ..
> Or allow to developer choose way.

I may not be understanding all the jargon, but I thought this is the way Valentina already works - using the best of both ways.  We can use the classes for some functions and the SQL for others.  This is what I am doing and it works nicely.

Steve


--
Steve Albin, Montclair, NJ
http://www.steve-albin.com
http://www.jazzdiscography.com