[IMP] core: introduce _field_to_sql() to replace _inherits_join_calc()

The new method should be used to generate an SQL object that represents
the value of a field in an SQL query.  Later this method will add
metadata to SQL objects, and that metadata will be used to determine
which fields to flush before executing some SQL code.

Part-of: odoo/odoo#138019

odoo/api.py

@@ -29,7 +29,7 @@ except ImportError:
     from decorator import decorator
 
 from .exceptions import AccessError, CacheMiss
-from .tools import classproperty, frozendict, lazy_property, OrderedSet, Query, StackMap
+from .tools import frozendict, lazy_property, OrderedSet, Query, SQL, StackMap
 from .tools.translate import _
 
 _logger = logging.getLogger(__name__)
@@ -1249,14 +1249,14 @@ class Cache(object):
 
             # select the column for the given ids
             query = Query(env.cr, model._table, model._table_query)
-            qname = model._inherits_join_calc(model._table, field.name, query)
+            sql_id = SQL.identifier(model._table, 'id')
+            sql_field = model._field_to_sql(model._table, field.name, query)
             if field.type == 'binary' and (
                 model.env.context.get('bin_size') or model.env.context.get('bin_size_' + field.name)
             ):
-                qname = f'pg_size_pretty(length({qname})::bigint)'
-            query.add_where(f'"{model._table}".id IN %s', [tuple(ids)])
-            query_str, params = query.select(f'"{model._table}".id', qname)
-            env.cr.execute(query_str, params)
+                sql_field = SQL('pg_size_pretty(length(%s)::bigint)', sql_field)
+            query.add_where(SQL("%s IN %s", sql_id, tuple(ids)))
+            env.cr.execute(query.select(sql_id, sql_field))
 
             # compare returned values with corresponding values in cache
             for id_, value in env.cr.fetchall():