Using Odoo(about Model)

Generally, the model file can be named as coolmodule.py (depends on you), the view file can be named as coolmodule.xml. In coolmodule.py, you can define model in this way(old api):

:::python

from openerp.osv import fields, osv

class cool_customer(osv.osv):
    _name = "cool.customer"
    _description = "YourDescriptions"

    def _default_title_id(self, cr, uid, context=None):
        #some code
        return title_id

    _columns = {
        'name' : fields.char('Name',required=True),
        'datetime': fields.datetime('DateTime'),
        'title': fields.many2one('cool.customer.title', 'Title'),
        'bank_ids': fields.one2many('cool.customer.bank', 'customer_id', 'Banks'),
        'comment': fields.text('Notes'),
        'active': fields.boolean('Active'),
        'type': fields.selection([('default', 'Default'), ('invoice', 'Invoice'),('delivery', 'Shipping'), ('contact', 'Contact'),('other', 'Other')], 'Address Type',help="SomeHelpText."),
        'category_id': fields.many2many('cool.costomer.category','coo_customer_category_rel', 'costomer_id', 'category_id', string='Tags'),
        #'display_name': fields.function(_display_name, type='char', string='Name', store=_display_name_store_triggers, select=True)
    }
    _defaults = {
        'datetime':fields.datetime.now,
        'active': True,
        'type': 'contact',
        'title': _default_title_id
    }


class cool_customer_title(osv.osv):
    _name = 'cool.custmoer.title'
    _order = 'name'
    _columns = {
        'name': fields.char('Title', required=True, translate=True),
        'shortcut': fields.char('Abbreviation', translate=True)
    }


class cool_customer_bank(osv.osv):
    _name = 'cool.customer.bank'
    _columns = {
        'name': fields.char('Title', required=True, translate=True),
        'code': fields.char('Code', size=64, required=True),
        'customer_id': fields.many2one('cool.customer', 'Account Owner', ondelete='cascade', select=True)
    }


class cool_customer_category(osv.osv):
    _name = 'cool.customer.category'
    _columns = {
    'name': fields.char('Category Name', required=True, translate=True),
    'customer_ids':fields.many2many('cool.costomer','coo_customer_category_rel', 'category_id', 'customer_id', string='Customers'),
    }

• _name = 'cool.customer' This defines the name of this model, and the name(cool\_customer) of table in database.
• _columns = {...} This defines the columns of the table cool_customer, different types as above. Notes the funtion field is a little complicated, I decide to talk it after this article.
• _defaults = {...} This defines the default value of columns or fields
• colums 'datetime': fields.datetime('DateTime') This defines the date type, and there is an other tpye called fileds.date('Datet'), and you can use 'date': fields.date.today to set the default date to today
• columns 'type': fields.selection([('default', 'Default'), ('invoice', 'Invoice'),('delivery', 'Shipping'), ('contact', 'Contact'),('other', 'Other')], 'Address Type',help"SomeHelpText."),= This defines a select coloums, when you have serverl certain options to pick, you can use this kind of field
• many2one relation Just like 'title': fields.many2one('cool.customer.title', 'Title') to define a many2one relation
• many2one relation The one side: 'bank_ids': fields.one2many('cool.customer.bank', 'customer_id', 'Banks') The many side: 'customer_id': fields.many2one('cool.customer', 'Account Owner', ondelete='cascade', select=True) ondelete='cascade': means if the record in one side is delete,what will do to the related many side? Other options are: 'null', default value is 'null'
• many2many relation 'category_id': fields.many2many('cool.costomer.category','coo_customer_category_rel', 'costomer_id', 'category_id', string'Tags'),= The cool.costomer.category defines the relation model, the coo_customer_category_rel defines the third relation table name between the two models, 'category_id', 'customer_id' definds the columns in coo_customer_category_rel,notice the order to point right model. You can also not write coo_customer_category_rel, category_id', 'customer_id to let odoo name for you, but if you have lots many2many relations, remember to point clearly.
• defaults : 'title': _default_title_id The default value of a field can also be a vale of funtion. Notice the definition of the function (such as _default_title_id here) should be above the place using it.