ORM-0.8

Changes for version 0.8 - 2005-12-04

original version; created by h2xs 1.23 with options -AX -n ORM
New features:
- Implemented reverse properties
- Implemented object linking on arbitrary properties
- Modify '_db_type_to_class' to accepts field_name and field_type arguments
- Implement transactions
- Modify ORM->stat to add ability to load several objects by one query
- Use cache in ORM::Db::DBI->select_full
- Implement object cache
- Deny use of intermediate classes without their own tables, because in opposite case when exist 2 intermediate classes derived from one base class then search through one of child classes also finds objects of second class.
- Implement use of ORM::Expr with 'update'
- Add SQL logging feature to ORM::Db
- Implement separate layer for DB operations
- Autoreconnect to SQL server after "Mysql server has gone away"
- Add method ORM->stat()
- Feature to use sealed classes (when primary table does not contain class field)
- Argument lazy_load to ORM->stat(), which allows to use lazy loaded objects
- Lazy loaded objects, implement 2 variants:
  - variant 1: known only 'id' and nothing loaded
  - variant 2: loaded only tables of primary class
- Use of third party classes as object properties
- Calculated meta-properties (ORM::Metaprop incapsulates ORM::Expr)
- ORM should log changes history via ORM::History
- Initial class configuration:
  - global parameter 'history_is_enabled'
  - posibility to enable/disable hostory on per class basis
  - global parameter 'emulate_foreign_keys'
  - method 'new', 'update', 'delete' should accept argument to enable/disable history for particular operation
- Implement object changes history
- Produce separate initial class from ORM for every separate object model
- Use ORM::Db->qt to quote table names, ORM::Db->qf to quote field names, ORM::Db->qi to quote aliases
- Use ORM::Db->qi to quote table names and field names
- Add redefineable method ORM->_db_type_to_class
Fixes:
- Delete method ORM::Metaprop->_expanded
- Reimplement table joins
- Fix automatic loading of related modules
- Modify 'update' method
  - Wrong compare of properties: $arg{prop}->{$prop} ne $self->{_ORM_data}->{$prop}
  - add check, whether object was changed after it was fetched from DB
  - ability to update objetc only when its properties are equal to those assumed by user
- Fix _validate_prop
- Fix ORM::Tjoin
- ORM::History->rollback should delete rolled back history entries from 'history' table
- Replace calls to isa to UNIVERSAL::isa
- Stop using obsoletted ORM::db_auth
- Move automatic init of 'cdate' properties from ORM to my initial class;