Model fields are defined as attributes on the model itself:

from odoo import models, fields
class AModel(models.Model):
    _name = 'a.model.name'

    field1 = fields.Char()


this means you cannot define a field and a method with the same name, the last one will silently overwrite the former ones.

By default, the field’s label (user-visible name) is a capitalized version of the field name, this can be overridden with the string parameter.

field2 = fields.Integer(string="Field Label")

For the list of field types and parameters, see the fields reference.

Default values are defined as parameters on fields, either as a value:

name = fields.Char(default="a value")

or as a function called to compute the default value, which should return that value:

def _default_name(self):
    return self.get_value()

name = fields.Char(default=lambda self: self._default_name())






Basic Fields

Advanced Fields

Date(time) Fields

Dates and Datetimes are very important fields in any kind of business application. Their misuse can create invisible yet painful bugs, this section aims to provide Odoo developers with the knowledge required to avoid misusing these fields.

When assigning a value to a Date/Datetime field, the following options are valid:

  • A date or datetime object.

  • A string in the proper server format:

    • YYYY-MM-DD for Date fields,

    • YYYY-MM-DD HH:MM:SS for Datetime fields.

  • False or None.

The Date and Datetime fields class have helper methods to attempt conversion into a compatible type:


To parse date/datetimes coming from external sources:


Date / Datetime comparison best practices:

  • Date fields can only be compared to date objects.

  • Datetime fields can only be compared to datetime objects.


Strings representing dates and datetimes can be compared between each other, however the result may not be the expected result, as a datetime string will always be greater than a date string, therefore this practice is heavily discouraged.

Common operations with dates and datetimes such as addition, subtraction or fetching the start/end of a period are exposed through both Date and Datetime. These helpers are also available by importing odoo.tools.date_utils.



Datetime fields are stored as timestamp without timezone columns in the database and are stored in the UTC timezone. This is by design, as it makes the Odoo database independent from the timezone of the hosting server system. Timezone conversion is managed entirely by the client side.

Relational Fields

Pseudo-relational fields

Computed Fields

Fields can be computed (instead of read straight from the database) using the compute parameter. It must assign the computed value to the field. If it uses the values of other fields, it should specify those fields using depends().

from odoo import api
total = fields.Float(compute='_compute_total')

@api.depends('value', 'tax')
def _compute_total(self):
    for record in self:
        record.total = record.value + record.value * record.tax
  • dependencies can be dotted paths when using sub-fields:

    def _compute_total(self):
        for record in self:
            record.total = sum(line.value for line in record.line_ids)
  • computed fields are not stored by default, they are computed and returned when requested. Setting store=True will store them in the database and automatically enable searching.

  • searching on a computed field can also be enabled by setting the search parameter. The value is a method name returning a Search domains.

    upper_name = field.Char(compute='_compute_upper', search='_search_upper')
    def _search_upper(self, operator, value):
        if operator == 'like':
            operator = 'ilike'
        return [('name', operator, value)]

    The search method is invoked when processing domains before doing an actual search on the model. It must return a domain equivalent to the condition: field operator value.

  • Computed fields are readonly by default. To allow setting values on a computed field, use the inverse parameter. It is the name of a function reversing the computation and setting the relevant fields:

    document = fields.Char(compute='_get_document', inverse='_set_document')
    def _get_document(self):
        for record in self:
            with open(record.get_document_path) as f:
                record.document = f.read()
    def _set_document(self):
        for record in self:
            if not record.document: continue
            with open(record.get_document_path()) as f:
  • multiple fields can be computed at the same time by the same method, just use the same method on all fields and set all of them:

    discount_value = fields.Float(compute='_apply_discount')
    total = fields.Float(compute='_apply_discount')
    @api.depends('value', 'discount')
    def _apply_discount(self):
        for record in self:
            # compute actual discount from discount percentage
            discount = record.value * record.discount
            record.discount_value = discount
            record.total = record.value - discount


While it is possible to use the same compute method for multiple fields, it is not recommended to do the same for the inverse method.

During the computation of the inverse, all fields that use said inverse are protected, meaning that they can’t be computed, even if their value is not in the cache.

If any of those fields is accessed and its value is not in cache, the ORM will simply return a default value of False for these fields. This means that the value of the inverse fields (other than the one triggering the inverse method) may not give their correct value and this will probably break the expected behavior of the inverse method.

Automatic fields


Identifier field

If length of current recordset is 1, return id of unique record in it.

Raise an Error otherwise.

Access Log fields

These fields are automatically set and updated if _log_access is enabled. It can be disabled to avoid creating or updating those fields on tables for which they are not useful.

By default, _log_access is set to the same value as _auto


Stores when the record was created, Datetime


Stores who created the record, Many2one to a res.users.


Stores when the record was last updated, Datetime


Stores who last updated the record, Many2one to a res.users.


_log_access must be enabled on TransientModel.

Reserved Field names

A few field names are reserved for pre-defined behaviors beyond that of automated fields. They should be defined on a model when the related behavior is desired:


default value for _rec_name, used to display records in context where a representative “naming” is necessary.



toggles the global visibility of the record, if active is set to False the record is invisible in most searches and listing.


Special methods:


lifecycle stages of the object, used by the states attribute on fields.



default_value of _parent_name, used to organize records in a tree structure and enables the child_of and parent_of operators in domains.



When _parent_store is set to True, used to store a value reflecting the tree structure of _parent_name, and to optimize the operators child_of and parent_of in search domains. It must be declared with index=True for proper operation.



Main field name used for Odoo multi-company behavior.

Used by :meth:~odoo.models._check_company to check multi company consistency. Defines whether a record is shared between companies (no value) or only accessible by the users of a given company.

Many2one :type: res_company


Interactions with models and records are performed through recordsets, an ordered collection of records of the same model.


Contrary to what the name implies, it is currently possible for recordsets to contain duplicates. This may change in the future.

Methods defined on a model are executed on a recordset, and their self is a recordset:

class AModel(models.Model):
    _name = 'a.model'
    def a_method(self):
        # self can be anything between 0 records and all records in the
        # database

Iterating on a recordset will yield new sets of a single record (“singletons”), much like iterating on a Python string yields strings of a single characters:

def do_operation(self):
    print(self) # => a.model(1, 2, 3, 4, 5)
    for record in self:
        print(record) # => a.model(1), then a.model(2), then a.model(3), ...

Field access

Recordsets provide an “Active Record” interface: model fields can be read and written directly from the record as attributes.


When accessing non-relational fields on a recordset of potentially multiple records, use mapped():

total_qty = sum(self.mapped('qty'))

Field values can also be accessed like dict items, which is more elegant and safer than getattr() for dynamic field names. Setting a field’s value triggers an update to the database:

>>> record.name
Example Name
>>> record.company_id.name
Company Name
>>> record.name = "Bob"
>>> field = "name"
>>> record[field]


Trying to read a field on multiple records will raise an error for non relational fields.

Accessing a relational field (Many2one, One2many, Many2many) always returns a recordset, empty if the field is not set.

Record cache and prefetching

Odoo maintains a cache for the fields of the records, so that not every field access issues a database request, which would be terrible for performance. The following example queries the database only for the first statement:

record.name             # first access reads value from database
record.name             # second access gets value from cache

To avoid reading one field on one record at a time, Odoo prefetches records and fields following some heuristics to get good performance. Once a field must be read on a given record, the ORM actually reads that field on a larger recordset, and stores the returned values in cache for later use. The prefetched recordset is usually the recordset from which the record comes by iteration. Moreover, all simple stored fields (boolean, integer, float, char, text, date, datetime, selection, many2one) are fetched altogether; they correspond to the columns of the model’s table, and are fetched efficiently in the same query.

Consider the following example, where partners is a recordset of 1000 records. Without prefetching, the loop would make 2000 queries to the database. With prefetching, only one query is made:

for partner in partners:
    print partner.name          # first pass prefetches 'name' and 'lang'
                                # (and other fields) on all 'partners'
    print partner.lang

The prefetching also works on secondary records: when relational fields are read, their values (which are records) are subscribed for future prefetching. Accessing one of those secondary records prefetches all secondary records from the same model. This makes the following example generate only two queries, one for partners and one for countries:

countries = set()
for partner in partners:
    country = partner.country_id        # first pass prefetches all partners
    countries.add(country.name)         # first pass prefetches all countries

Method decorators


>>> records.env
<Environment object ...>
>>> records.env.uid
>>> records.env.user
>>> records.env.cr
<Cursor object ...>

When creating a recordset from an other recordset, the environment is inherited. The environment can be used to get an empty recordset in an other model, and query that model:

>>> self.env['res.partner']
>>> self.env['res.partner'].search([('is_company', '=', True), ('customer', '=', True)])
res.partner(7, 18, 12, 14, 17, 19, 8, 31, 26, 16, 13, 20, 30, 22, 29, 15, 23, 28, 74)

Some lazy properties are available to access the environment (contextual) data:

Useful environment methods

Altering the environment

SQL Execution

The cr attribute on environments is the cursor for the current database transaction and allows executing SQL directly, either for queries which are difficult to express using the ORM (e.g. complex joins) or for performance reasons:

self.env.cr.execute("some_sql", params)


Executing raw SQL bypasses the ORM and, by consequent, Odoo security rules. Please make sure your queries are sanitized when using user input and prefer using ORM utilities if you don’t really need to use SQL queries.

One important thing to know about models is that they don’t necessarily perform database updates right away. Indeed, for performance reasons, the framework delays the recomputation of fields after modifying records. And some database updates are delayed, too. Therefore, before querying the database, one has to make sure that it contains the relevant data for the query. This operation is called flushing and performs the expected database updates.


# make sure that 'partner_id' is up-to-date in database

self.env.cr.execute("SELECT id FROM model WHERE partner_id IN %s", [ids])
ids = [row[0] for row in self.env.cr.fetchall()]

Before every SQL query, one has to flush the data needed for that query. There are three levels for flushing, each with its own API. One can flush either everything, all the records of a model, or some specific records. Because delaying updates improves performance in general, we recommend to be specific when flushing.

Because models use the same cursor and the Environment holds various caches, these caches must be invalidated when altering the database in raw SQL, or further uses of models may become incoherent. It is necessary to clear caches when using CREATE, UPDATE or DELETE in SQL, but not SELECT (which simply reads the database).


# make sure 'state' is up-to-date in database

self.env.cr.execute("UPDATE model SET state=%s WHERE state=%s", ['new', 'old'])

# invalidate 'state' from the cache

Just like flushing, one can invalidate either the whole cache, the cache of all the records of a model, or the cache of specific records. One can even invalidate specific fields on some records or all records of a model. As the cache improves performance in general, we recommend to be specific when invalidating.

The methods above keep the caches and the database consistent with each other. However, if computed field dependencies have been modified in the database, one has to inform the models for the computed fields to be recomputed. The only thing the framework needs to know is what fields have changed on which records.


# make sure 'state' is up-to-date in database

# use the RETURNING clause to retrieve which rows have changed
self.env.cr.execute("UPDATE model SET state=%s WHERE state=%s RETURNING id", ['new', 'old'])
ids = [row[0] for row in self.env.cr.fetchall()]

# invalidate the cache, and notify the update to the framework
records = self.env['model'].browse(ids)

One has to figure out which records have been modified. There are many ways to do this, possibly involving extra SQL queries. In the example above, we take advantage of the RETURNING clause of PostgreSQL to retrieve the information without an extra query. After making the cache consistent by invalidation, invoke the method modified on the modified records with the fields that have been updated.

Common ORM methods




Search domains

A domain is a list of criteria, each criterion being a triple (either a list or a tuple) of (field_name, operator, value) where:

  • field_name (str)

    a field name of the current model, or a relationship traversal through a Many2one using dot-notation e.g. 'street' or 'partner_id.country'

  • operator (str)

    an operator used to compare the field_name with the value. Valid operators are:


    equals to


    not equals to


    greater than


    greater than or equal to


    less than


    less than or equal to


    unset or equals to (returns true if value is either None or False, otherwise behaves like =)


    matches field_name against the value pattern. An underscore _ in the pattern stands for (matches) any single character; a percent sign % matches any string of zero or more characters.


    matches field_name against the %value% pattern. Similar to =like but wraps value with ‘%’ before matching

    not like

    doesn’t match against the %value% pattern


    case insensitive like

    not ilike

    case insensitive not like


    case insensitive =like


    is equal to any of the items from value, value should be a list of items

    not in

    is unequal to all of the items from value


    is a child (descendant) of a value record (value can be either one item or a list of items).

    Takes the semantics of the model into account (i.e following the relationship field named by _parent_name).


    is a parent (ascendant) of a value record (value can be either one item or a list of items).

    Takes the semantics of the model into account (i.e following the relationship field named by _parent_name).

  • value

    variable type, must be comparable (through operator) to the named field.

Domain criteria can be combined using logical operators in prefix form:


logical AND, default operation to combine criteria following one another. Arity 2 (uses the next 2 criteria or combinations).


logical OR, arity 2.


logical NOT, arity 1.


Mostly to negate combinations of criteria Individual criterion generally have a negative form (e.g. = -> !=, < -> >=) which is simpler than negating the positive.


To search for partners named ABC, from belgium or germany, whose language is not english:


This domain is interpreted as:

    (name is 'ABC')
AND (language is NOT english)
AND (country is Belgium OR Germany)

Record(set) information


Returns the environment of the given recordset.




Recordsets are immutable, but sets of the same model can be combined using various set operations, returning new recordsets.

  • record in set returns whether record (which must be a 1-element recordset) is present in set. record not in set is the inverse operation

  • set1 <= set2 and set1 < set2 return whether set1 is a subset of set2 (resp. strict)

  • set1 >= set2 and set1 > set2 return whether set1 is a superset of set2 (resp. strict)

  • set1 | set2 returns the union of the two recordsets, a new recordset containing all records present in either source

  • set1 & set2 returns the intersection of two recordsets, a new recordset containing only records present in both sources

  • set1 - set2 returns a new recordset containing only records of set1 which are not in set2

Recordsets are iterable so the usual Python tools are available for transformation (map(), sorted(), ifilter(), …) however these return either a list or an iterator, removing the ability to call methods on their result, or to use set operations.

Recordsets therefore provide the following operations returning recordsets themselves (when possible):




Since V13, multi-relational field access is supported and works like a mapped call:

records.partner_id  # == records.mapped('partner_id')
records.partner_id.bank_ids  # == records.mapped('partner_id.bank_ids')
records.partner_id.mapped('name')  # == records.mapped('partner_id.name')


Inheritance and extension

Odoo provides three different mechanisms to extend models in a modular way:

  • creating a new model from an existing one, adding new information to the copy but leaving the original module as-is

  • extending models defined in other modules in-place, replacing the previous version

  • delegating some of the model’s fields to records it contains


Classical inheritance

When using the _inherit and _name attributes together, Odoo creates a new model using the existing one (provided via _inherit) as a base. The new model gets all the fields, methods and meta-information (defaults & al) from its base.

class Inheritance0(models.Model):
    _name = 'inheritance.0'
    _description = 'Inheritance Zero'

    name = fields.Char()

    def call(self):
        return self.check("model 0")

    def check(self, s):
        return "This is {} record {}".format(s, self.name)

class Inheritance1(models.Model):
    _name = 'inheritance.1'
    _inherit = 'inheritance.0'
    _description = 'Inheritance One'

    def call(self):
        return self.check("model 1")

and using them:

a = env['inheritance.0'].create({'name': 'A'})
b = env['inheritance.1'].create({'name': 'B'})


will yield:

“This is model 0 record A” “This is model 1 record B”

the second model has inherited from the first model’s check method and its name field, but overridden the call method, as when using standard Python inheritance.


When using _inherit but leaving out _name, the new model replaces the existing one, essentially extending it in-place. This is useful to add new fields or methods to existing models (created in other modules), or to customize or reconfigure them (e.g. to change their default sort order):

class Extension0(models.Model):
_name = 'extension.0'
_description = 'Extension zero'

name = fields.Char(default="A")

class Extension1(models.Model):
_inherit = 'extension.0'

description = fields.Char(default="Extended")
record = env['extension.0'].create({})

will yield:

{'name': "A", 'description': "Extended"}


It will also yield the various automatic fields unless they’ve been disabled


The third inheritance mechanism provides more flexibility (it can be altered at runtime) but less power: using the _inherits a model delegates the lookup of any field not found on the current model to “children” models. The delegation is performed via Reference fields automatically set up on the parent model.

The main difference is in the meaning. When using Delegation, the model has one instead of is one, turning the relationship in a composition instead of inheritance:

class Screen(models.Model):
    _name = 'delegation.screen'
    _description = 'Screen'

    size = fields.Float(string='Screen Size in inches')

class Keyboard(models.Model):
    _name = 'delegation.keyboard'
    _description = 'Keyboard'

    layout = fields.Char(string='Layout')

class Laptop(models.Model):
    _name = 'delegation.laptop'
    _description = 'Laptop'

    _inherits = {
        'delegation.screen': 'screen_id',
        'delegation.keyboard': 'keyboard_id',

    name = fields.Char(string='Name')
    maker = fields.Char(string='Maker')

    # a Laptop has a screen
    screen_id = fields.Many2one('delegation.screen', required=True, ondelete="cascade")
    # a Laptop has a keyboard
    keyboard_id = fields.Many2one('delegation.keyboard', required=True, ondelete="cascade")
record = env['delegation.laptop'].create({
    'screen_id': env['delegation.screen'].create({'size': 13.0}).id,
    'keyboard_id': env['delegation.keyboard'].create({'layout': 'QWERTY'}).id,

will result in:


and it’s possible to write directly on the delegated field:

record.write({'size': 14.0})


when using delegation inheritance, methods are not inherited, only fields


  • _inherits is more or less implemented, avoid it if you can;

  • chained _inherits is essentially not implemented, we cannot guarantee anything on the final behavior.

Fields Incremental Definition

A field is defined as class attribute on a model class. If the model is extended, one can also extend the field definition by redefining a field with the same name and same type on the subclass. In that case, the attributes of the field are taken from the parent class and overridden by the ones given in subclasses.

For instance, the second class below only adds a tooltip on the field state:

class First(models.Model):
    _name = 'foo'
    state = fields.Selection([...], required=True)

class Second(models.Model):
    _inherit = 'foo'
    state = fields.Selection(help="Blah blah blah")

Error management