@api.model

    @api.returns('self',upgrade=lambda self, value, args, offset=0, limit=None, order=None, count=False: value if count else self.browse(value),

        downgrade=lambda self, value, args, offset=0, limit=None, order=None, count=False: value if count else value.ids)

    def search(self, args, offset=0, limit=None, order=None, count=False):

        """ search(args[, offset=0][, limit=None][, order=None][, count=False])

        Searches for records based on the ``args``

        :ref:`search domain `.

        :param args: :ref:`A search domain `. Use an empty

                     list to match all records.    查询domain，使用空列表 [] 来查询所有的记录

        :param int offset: number of results to ignore (default: none)    跳过多少查询记录

        :param int limit: maximum number of records to return (default: all)  查询多少条数据

        :param str order: sort string   查询记录的排序方式

        :param bool count: if True, only counts and returns the number of matching records (default: False) 如果为True，则查询匹配记录的数量

        :returns: at most ``limit`` records matching the search criteria  返回limit内的匹配记录的数据记录集

        :raise AccessError: * if user tries to bypass access rules for read on the requested object. 如果用户试图绕过访问规则来读取请求的对象将会报错

        """

        # 返回根据domain查询的记录ids

        res = self._search(args, offset=offset, limit=limit, order=order, count=count)

        # 如果count = True，则返回记录数量，否则返回记录集

        return res if count else self.browse(res)

  @api.model

    def _search(self, args, offset=0, limit=None, order=None, count=False, access_rights_uid=None):

        """

        Private implementation of search() method, allowing specifying the uid to use for the access right check.

        This is useful for example when filling in the selection list for a drop-down and avoiding access rights errors,

        by specifying ``access_rights_uid=1`` to bypass access rights check, but not ir.rules!

        This is ok at the security level because this method is private and not callable through XML-RPC.

            search()方法的私有实现，允许指定用于访问权检查的uid。

            这很有用，例如在为下拉列表填写选择列表和避免访问权限错误时，

            通过指定' access_rights_uid=1 ' 绕过访问权限检查，而不是ir.rules!

            这在安全级别上是可以的，因为这个方法是私有的，不能通过XML-RPC调用。

        :param access_rights_uid: optional user ID to use when checking access rights 检查访问权限时使用的可选用户ID

                                  (not for ir.rules, this is only for ir.model.access) 不是针对ir.rules，这只是针对ir.model.access

        :return: a list of record ids or an integer (if count is True)

        """

        self.sudo(access_rights_uid or self._uid).check_access_rights('read')

        if expression.is_false(self, args):

            # 查询条件表达式为空，则不进行查询

            # optimization: no need to query, as no record satisfies the domain

             # 优化: 不需要查询，因为没有记录满足domain

            return 0 if count else []

        # 得到查询sql

        query = self._where_calc(args)

        self._apply_ir_rules(query, 'read')

        # 增加查询sql的排序条件

        order_by = self._generate_order_by(order, query)

        # from条件部分 和 where条件部分 及 条件值

        from_clause, where_clause, where_clause_params = query.get_sql()

        where_str = where_clause and (" WHERE %s" % where_clause) or ''

        # 如果count=True、则返回满组条件的记录数

        if count:

            # Ignore order, limit and offset when just counting, they don't make sense and could

            # hurt performance

            query_str = 'SELECT count(1) FROM ' + from_clause + where_str

            self._cr.execute(query_str, where_clause_params)

            res = self._cr.fetchone()

            return res[0]

        limit_str = limit and ' limit %d' % limit or ''

        offset_str = offset and ' offset %d' % offset or ''

        query_str = 'SELECT "%s".id FROM ' % self._table + from_clause + where_str + order_by + limit_str + offset_str

        self._cr.execute(query_str, where_clause_params)

        res = self._cr.fetchall()

        # TDE note: with auto_join, we could have several lines about the same result  使用auto_join，我们可以有几行关于相同结果的代码

        # i.e. a lead with several unread messages; we uniquify the result using  带有若干未读消息的前导;我们统一了使用的结果

        # a fast way to do it while preserving order (http://www.peterbe.com/plog/uniqifiers-benchmark) 一个快速的方法，同时保持秩序

        def _uniquify_list(seq):

            seen = set()

            # 如果不在加到set里边，在了就不再重复统计

            return [x for x in seq if x not in seen and not seen.add(x)]

        # 返回去重的ids

        return _uniquify_list([x[0] for x in res])

 @api.model

    def _where_calc(self, domain, active_test=True):

        """Computes the WHERE clause needed to implement an OpenERP domain.

        :param domain: the domain to compute

        :type domain: list

        :param active_test: whether the default filtering of records with ``active``

                            field set to ``False`` should be applied.

        :return: the query expressing the given domain as provided in domain

        :rtype: osv.query.Query

        """

        # if the object has a field named 'active', filter out all inactive 如果对象有一个名为“active”的字段，则过滤掉所有

        # records unless they were explicitely asked for 非活动的字段记录，除非他们明确要求

        # 模型中存在active字段，并且 active_test = True 并且 上下文中也获取到active_test = True，则过滤掉active!=1的记录

        if 'active' in self._fields and active_test and self._context.get('active_test', True):

            # the item[0] trick below works for domain items and '&'/'|'/'!'

            # operators too

            if not any(item[0] == 'active' for item in domain):

                domain = [('active', '=', 1)] + domain

        if domain:

            # 解析domian表达式

            e = expression.expression(domain, self)

            # 获取到表

            tables = e.get_tables()

            # 将条件转化为sql查询条条件

            where_clause, where_params = e.to_sql()

            where_clause = [where_clause] if where_clause else []

        else:

            where_clause, where_params, tables = [], [], ['"%s"' % self._table]

        return Query(tables, where_clause, where_params)

@api.model

    def _generate_order_by(self, order_spec, query):

        """

        Attempt to construct an appropriate ORDER BY clause based on order_spec, which must be

        a comma-separated list of valid field names, optionally followed by an ASC or DESC direction.

        尝试基于order_spec构造适当的ORDER BY子句，必须是有效字段名的逗号分隔列表，可选地后跟ASC或DESC方向。

        :raise ValueError in case order_spec is malformed  order_spec格式错误会ValueError

        """

        order_by_clause = ''

        # 排序条件，如果存在则取，不存在的取模型定义的时候的顺序

        order_spec = order_spec or self._order

        if order_spec:

            # _generate_order_by_inner方法将order条件拼接成sql样式排序语句

            order_by_elements = self._generate_order_by_inner(self._table, order_spec, query)

            if order_by_elements:

                order_by_clause = ",".join(order_by_elements)

        return order_by_clause and (' ORDER BY %s ' % order_by_clause) or ''

 @api.model

    def search_count(self, args):

        """ search_count(args) -> int

            根据search的结果进行统计

        Returns the number of records in the current model matching :ref:`the

        provided domain `.

        """

        res = self.search(args, count=True)

        return res if isinstance(res, pycompat.integer_types) else len(res)

先进行search() 然后进行 read()

    @api.model

    def search_read(self, domain=None, fields=None, offset=0, limit=None, order=None):

        """

        Performs a ``search()`` followed by a ``read()``.  先search再read

        :param domain: Search domain, see ``args`` parameter in ``search()``. Defaults to an empty domain that will match all records.

            查询条件，条件为空默认查询全部

        :param fields: List of fields to read, see ``fields`` parameter in ``read()``. Defaults to all fields.

            查询的字段，默认全部字段

        :param offset: Number of records to skip, see ``offset`` parameter in ``search()``. Defaults to 0.

            跳过的数据量

        :param limit: Maximum number of records to return, see ``limit`` parameter in ``search()``. Defaults to no limit.

            查询的条数

        :param order: Columns to sort result, see ``order`` parameter in ``search()``. Defaults to no sort.

            排序条件

        :return: List of dictionaries containing the asked fields.

            返回字段的字典值列表

        :rtype: List of dictionaries. 包含字典的列表

        """

        records = self.search(domain or [], offset=offset, limit=limit, order=order)

        if not records:

            return []

        if fields and fields == ['id']:

            # shortcut read if we only want the ids

            return [{'id': record.id} for record in records]

        # read() ignores active_test, but it would forward it to any downstream search call

        # (e.g. for x2m or function fields), and this is not the desired behavior, the flag

        # was presumably only meant for the main search().

        # read()忽略active_test，但它会将其转发到任何下游搜索调用(例如，对于x2m或函数字，

        # 这不是期望的行为，这个标志可能只针对主搜索()。

        # TODO: Move this to read() directly?

        if 'active_test' in self._context:

            context = dict(self._context)

            del context['active_test']

            records = records.with_context(context)

        result = records.read(fields)

        if len(result) <= 1:

            return result

        # reorder read

        index = {vals['id']: vals for vals in result}

        return [index[record.id] for record in records if record.id in index]

  @api.model

    def name_search(self, name='', args=None, operator='ilike', limit=100):

        """ name_search(name='', args=None, operator='ilike', limit=100) -> records

        Search for records that have a display name matching the given

        ``name`` pattern when compared with the given ``operator``, while also

        matching the optional search domain (``args``).

            搜索具有与给定名称匹配的显示名称的记录“name”模式与给定的“operator”模式进行比较时，同时也是匹配可选搜索域(' ' args ' ')。

        This is used for example to provide suggestions based on a partial

        value for a relational field. Sometimes be seen as the inverse

        function of :meth:`~.name_get`, but it is not guaranteed to be.

            例如，它用于根据部分内容提供建议关系字段的值。有时被看作是相反的的函数:' ~.name_get '，但它不能保证是。

        This method is equivalent to calling :meth:`~.search` with a search

        domain based on ``display_name`` and then :meth:`~.name_get` on the

        result of the search.

            这个方法相当于调用:meth:' ~.search来搜索的域名，然后是:meth: ' ~.name_get '搜索结果。

        :param str name: the name pattern to match  用于搜索的名称

        :param list args: optional search domain (see :meth:`~.search` for

                          syntax), specifying further restrictions   搜索条件

        :param str operator: domain operator for matching ``name``, such as

                             ``'like'`` or ``'='``.  条件：like、=

        :param int limit: optional max number of records to return  查询的条数

        :rtype: list

        :return: list of pairs ``(id, text_repr)`` for all matching records.

        """

        return self._name_search(name, args, operator, limit=limit)

    @api.model

    def _name_search(self, name='', args=None, operator='ilike', limit=100, name_get_uid=None):

        # private implementation of name_search, allows passing a dedicated user

        # for the name_get part to solve some access rights issues

        args = list(args or [])

        # optimize out the default criterion of ``ilike ''`` that matches everything

        if not self._rec_name:

            _logger.warning("Cannot execute name_search, no _rec_name defined on %s", self._name)

        elif not (name == '' and operator == 'ilike'):

            args += [(self._rec_name, operator, name)]

        access_rights_uid = name_get_uid or self._uid

        ids = self._search(args, limit=limit, access_rights_uid=access_rights_uid)

        recs = self.browse(ids)

        return lazy_name_get(recs.sudo(access_rights_uid))

@api.model

    def read_group(self, domain, fields, groupby, offset=0, limit=None, orderby=False, lazy=True):

        """

        Get the list of records in list view grouped by the given ``groupby`` fields

            获取列表视图中按给定的“groupby”字段分组的记录列表

        :param domain: list specifying search criteria [['field_name', 'operator', 'value'], ...]

            domain条件

        :param list fields: list of fields present in the list view specified on the object.

                Each element is either 'field' (field name, using the default aggregation),

                or 'field:agg' (aggregate field with aggregation function 'agg'),

                or 'name:agg(field)' (aggregate field with 'agg' and return it as 'name').

                The possible aggregation functions are the ones provided by PostgreSQL

                (https://www.postgresql.org/docs/current/static/functions-aggregate.html)

                and 'count_distinct', with the expected meaning.

                分组之后显示的字段

        :param list groupby: list of groupby descriptions by which the records will be grouped.  

                A groupby description is either a field (then it will be grouped by that field)

                or a string 'field:groupby_function'.  Right now, the only functions supported

                are 'day', 'week', 'month', 'quarter' or 'year', and they only make sense for 

                date/datetime fields.

                分组条件

        :param int offset: optional number of records to skip

            跳过多少查询记录

        :param int limit: optional max number of records to return

            返回的记录数

        :param list orderby: optional ``order by`` specification, for

                             overriding the natural sort ordering of the

                             groups, see also :py:meth:`~osv.osv.osv.search`

                             (supported only for many2one fields currently)

            排序条件

        :param bool lazy: if true, the results are only grouped by the first groupby and the 

                remaining groupbys are put in the __context key.  If false, all the groupbys are

                done in one call.

                是否弃用懒加载:如果为真，则结果仅按第一个groupby和其余的组放在__context键中。如果为假，则所有组都是一次调用搞定。

        :return: list of dictionaries(one dictionary for each record) containing:

                    * the values of fields grouped by the fields in ``groupby`` argument

                    * __domain: list of tuples specifying the search criteria

                    * __context: dictionary with argument like ``groupby``

        :rtype: [{'field_name_1': value, ...]

        :raise AccessError: * if user has no read rights on the requested object

                            * if user tries to bypass access rules for read on the requested object

        """

        result = self._read_group_raw(domain, fields, groupby, offset=offset, limit=limit, orderby=orderby, lazy=lazy)

        groupby = [groupby] if isinstance(groupby, pycompat.string_types) else list(OrderedSet(groupby))

        dt = [

            f for f in groupby

            if self._fields[f.split(':')[0]].type in ('date', 'datetime')    # e.g. 'date:month'

        ]

        # iterate on all results and replace the "full" date/datetime value

        # (range, label) by just the formatted label, in-place

        for group in result:

            for df in dt:

                # could group on a date(time) field which is empty in some

                # records, in which case as with m2o the _raw value will be

                # `False` instead of a (value, label) pair. In that case,

                # leave the `False` value alone

                if group.get(df):

                    group[df] = group[df][1]

        return result

    @api.model

    def _read_group_raw(self, domain, fields, groupby, offset=0, limit=None, orderby=False, lazy=True):

        self.check_access_rights('read')

        # domian解析为sql查询语句

        query = self._where_calc(domain)

        # 拿出存储数据库的字段

        fields = fields or [f.name for f in self._fields.values() if f.store]

        groupby = [groupby] if isinstance(groupby, pycompat.string_types) else list(OrderedSet(groupby))

        groupby_list = groupby[:1] if lazy else groupby

        annotated_groupbys = [self._read_group_process_groupby(gb, query) for gb in groupby_list]

        groupby_fields = [g['field'] for g in annotated_groupbys]

        order = orderby or ','.join([g for g in groupby_list])

        groupby_dict = {gb['groupby']: gb for gb in annotated_groupbys}

        self._apply_ir_rules(query, 'read')

        for gb in groupby_fields:

            assert gb in self._fields, "Unknown field %r in 'groupby'" % gb

            gb_field = self._fields[gb].base_field

            assert gb_field.store and gb_field.column_type, "Fields in 'groupby' must be regular database-persisted fields (no function or related fields), or function fields with store=True"

        aggregated_fields = []

        select_terms = []

        for fspec in fields:

            if fspec == 'sequence':

                continue

            match = regex_field_agg.match(fspec)

            if not match:

                raise UserError(_("Invalid field specification %r.") % fspec)

            name, func, fname = match.groups()

            if func:

                # we have either 'name:func' or 'name:func(fname)'

                fname = fname or name

                field = self._fields[fname]

                if not (field.base_field.store and field.base_field.column_type):

                    raise UserError(_("Cannot aggregate field %r.") % fname)

                if not func.isidentifier():

                    raise UserError(_("Invalid aggregation function %r.") % func)

            else:

                # we have 'name', retrieve the aggregator on the field

                field = self._fields.get(name)

                if not (field and field.base_field.store and

                        field.base_field.column_type and field.group_operator):

                    continue

                func, fname = field.group_operator, name

            if fname in groupby_fields:

                continue

            if name in aggregated_fields:

                raise UserError(_("Output name %r is used twice.") % name)

            aggregated_fields.append(name)

            expr = self._inherits_join_calc(self._table, fname, query)

            if func.lower() == 'count_distinct':

                term = 'COUNT(DISTINCT %s) AS "%s"' % (expr, name)

            else:

                term = '%s(%s) AS "%s"' % (func, expr, name)

            select_terms.append(term)

        for gb in annotated_groupbys:

            select_terms.append('%s as "%s" ' % (gb['qualified_field'], gb['groupby']))

        groupby_terms, orderby_terms = self._read_group_prepare(order, aggregated_fields, annotated_groupbys, query)

        from_clause, where_clause, where_clause_params = query.get_sql()

        if lazy and (len(groupby_fields) >= 2 or not self._context.get('group_by_no_leaf')):

            count_field = groupby_fields[0] if len(groupby_fields) >= 1 else '_'

        else:

            count_field = '_'

        count_field += '_count'

        prefix_terms = lambda prefix, terms: (prefix + " " + ",".join(terms)) if terms else ''

        prefix_term = lambda prefix, term: ('%s %s' % (prefix, term)) if term else ''

        query = """

            SELECT min("%(table)s".id) AS id, count("%(table)s".id) AS "%(count_field)s" %(extra_fields)s

            FROM %(from)s

            %(where)s

            %(groupby)s

            %(orderby)s

            %(limit)s

            %(offset)s

        """ % {

            'table': self._table,

            'count_field': count_field,

            'extra_fields': prefix_terms(',', select_terms),

            'from': from_clause,

            'where': prefix_term('WHERE', where_clause),

            'groupby': prefix_terms('GROUP BY', groupby_terms),

            'orderby': prefix_terms('ORDER BY', orderby_terms),

            'limit': prefix_term('LIMIT', int(limit) if limit else None),

            'offset': prefix_term('OFFSET', int(offset) if limit else None),

        }

        self._cr.execute(query, where_clause_params)

        fetched_data = self._cr.dictfetchall()

        if not groupby_fields:

            return fetched_data

        self._read_group_resolve_many2one_fields(fetched_data, annotated_groupbys)

        data = [{k: self._read_group_prepare_data(k, v, groupby_dict) for k, v in r.items()} for r in fetched_data]

        if self.env.context.get('fill_temporal') and data:

            data = self._read_group_fill_temporal(data, groupby, aggregated_fields,

                                                  annotated_groupbys)

        result = [self._read_group_format_result(d, annotated_groupbys, groupby, domain) for d in data]

        if lazy:

            # Right now, read_group only fill results in lazy mode (by default).

            # If you need to have the empty groups in 'eager' mode, then the

            # method _read_group_fill_results need to be completely reimplemented

            # in a sane way 

            result = self._read_group_fill_results(

                domain, groupby_fields[0], groupby[len(annotated_groupbys):],

                aggregated_fields, count_field, result, read_group_order=order,

            )

        return result