def test_statement(self):
ist = InsertStatement('table', None)
ist.add_assignment_clause(AssignmentClause('a', 'b'))
ist.add_assignment_clause(AssignmentClause('c', 'd'))
self.assertEqual(six.text_type(ist),
'INSERT INTO table ("a", "c") VALUES (%(0)s, %(1)s)')
def test_rendering(self):
us = UpdateStatement('table')
us.add_assignment_clause(AssignmentClause('a', 'b'))
us.add_assignment_clause(AssignmentClause('c', 'd'))
us.add_where_clause(WhereClause('a', EqualsOperator(), 'x'))
self.assertEqual(
six.text_type(us),
'UPDATE table SET "a" = %(0)s, "c" = %(1)s WHERE "a" = %(2)s',
six.text_type(us))
def test_context_update(self):
us = UpdateStatement('table')
us.add_assignment_clause(AssignmentClause('a', 'b'))
us.add_assignment_clause(AssignmentClause('c', 'd'))
us.add_where_clause(WhereClause('a', EqualsOperator(), 'x'))
us.update_context_id(3)
self.assertEqual(
six.text_type(us),
'UPDATE table SET "a" = %(4)s, "c" = %(5)s WHERE "a" = %(3)s')
self.assertEqual(us.get_context(), {'4': 'b', '5': 'd', '3': 'x'})
def test_context_update(self):
ist = InsertStatement('table', None)
ist.add_assignment_clause(AssignmentClause('a', 'b'))
ist.add_assignment_clause(AssignmentClause('c', 'd'))
ist.update_context_id(4)
self.assertEqual(six.text_type(ist),
'INSERT INTO table ("a", "c") VALUES (%(4)s, %(5)s)')
ctx = ist.get_context()
self.assertEqual(ctx, {'4': 'b', '5': 'd'})
def save(self):
"""
Creates / updates a row.
This is a blind insert call.
All validation and cleaning needs to happen
prior to calling this.
"""
if self.instance is None:
raise CQLEngineException("DML Query intance attribute is None")
assert type(self.instance) == self.model
nulled_fields = set()
if self.instance._has_counter or self.instance._can_update():
if self.instance._has_counter:
warn(
"'create' and 'save' actions on Counters are deprecated. A future version will disallow this. Use the 'update' mechanism instead."
)
return self.update()
else:
insert = InsertStatement(self.column_family_name,
ttl=self._ttl,
timestamp=self._timestamp,
if_not_exists=self._if_not_exists)
static_save_only = False if len(
self.instance._clustering_keys) == 0 else True
for name, col in self.instance._clustering_keys.items():
static_save_only = static_save_only and col._val_is_null(
getattr(self.instance, name, None))
for name, col in self.instance._columns.items():
if static_save_only and not col.static and not col.partition_key:
continue
val = getattr(self.instance, name, None)
if col._val_is_null(val):
if self.instance._values[name].changed:
nulled_fields.add(col.db_field_name)
continue
insert.add_assignment_clause(
AssignmentClause(
col.db_field_name,
col.to_database(getattr(self.instance, name, None))))
# skip query execution if it's empty
# caused by pointless update queries
if not insert.is_empty:
self._execute(insert)
# delete any nulled columns
if not static_save_only:
self._delete_null_columns()
def test_additional_rendering(self):
us = UpdateStatement('table', ttl=60)
us.add_assignment_clause(AssignmentClause('a', 'b'))
us.add_where_clause(WhereClause('a', EqualsOperator(), 'x'))
self.assertIn('USING TTL 60', six.text_type(us))
def test_context(self):
us = UpdateStatement('table')
us.add_assignment_clause(AssignmentClause('a', 'b'))
us.add_assignment_clause(AssignmentClause('c', 'd'))
us.add_where_clause(WhereClause('a', EqualsOperator(), 'x'))
self.assertEqual(us.get_context(), {'0': 'b', '1': 'd', '2': 'x'})
def update(self, **values):
"""
Performs an update on the row selected by the queryset. Include values to update in the
update like so:
.. code-block:: python
Model.objects(key=n).update(value='x')
Passing in updates for columns which are not part of the model will raise a ValidationError.
Per column validation will be performed, but instance level validation will not
(i.e., `Model.validate` is not called). This is sometimes referred to as a blind update.
For example:
.. code-block:: python
class User(Model):
id = Integer(primary_key=True)
name = Text()
setup(["localhost"], "test")
sync_table(User)
u = User.create(id=1, name="jon")
User.objects(id=1).update(name="Steve")
# sets name to null
User.objects(id=1).update(name=None)
Also supported is blindly adding and removing elements from container columns,
without loading a model instance from Cassandra.
Using the syntax `.update(column_name={x, y, z})` will overwrite the contents of the container, like updating a
non container column. However, adding `__<operation>` to the end of the keyword arg, makes the update call add
or remove items from the collection, without overwriting then entire column.
Given the model below, here are the operations that can be performed on the different container columns:
.. code-block:: python
class Row(Model):
row_id = columns.Integer(primary_key=True)
set_column = columns.Set(Integer)
list_column = columns.List(Integer)
map_column = columns.Map(Integer, Integer)
:class:`~cqlengine.columns.Set`
- `add`: adds the elements of the given set to the column
- `remove`: removes the elements of the given set to the column
.. code-block:: python
# add elements to a set
Row.objects(row_id=5).update(set_column__add={6})
# remove elements to a set
Row.objects(row_id=5).update(set_column__remove={4})
:class:`~cqlengine.columns.List`
- `append`: appends the elements of the given list to the end of the column
- `prepend`: prepends the elements of the given list to the beginning of the column
.. code-block:: python
# append items to a list
Row.objects(row_id=5).update(list_column__append=[6, 7])
# prepend items to a list
Row.objects(row_id=5).update(list_column__prepend=[1, 2])
:class:`~cqlengine.columns.Map`
- `update`: adds the given keys/values to the columns, creating new entries if they didn't exist, and overwriting old ones if they did
.. code-block:: python
# add items to a map
Row.objects(row_id=5).update(map_column__update={1: 2, 3: 4})
"""
if not values:
return
nulled_columns = set()
us = UpdateStatement(self.column_family_name,
where=self._where,
ttl=self._ttl,
timestamp=self._timestamp,
transactions=self._transaction)
for name, val in values.items():
col_name, col_op = self._parse_filter_arg(name)
col = self.model._columns.get(col_name)
# check for nonexistant columns
if col is None:
raise ValidationError("{}.{} has no column named: {}".format(
self.__module__, self.model.__name__, col_name))
# check for primary key update attempts
if col.is_primary_key:
raise ValidationError(
"Cannot apply update to primary key '{}' for {}.{}".format(
col_name, self.__module__, self.model.__name__))
# we should not provide default values in this use case.
val = col.validate(val)
if val is None:
nulled_columns.add(col_name)
continue
# add the update statements
if isinstance(col, columns.Counter):
# TODO: implement counter updates
raise NotImplementedError
elif isinstance(col, (columns.List, columns.Set, columns.Map)):
if isinstance(col, columns.List):
klass = ListUpdateClause
elif isinstance(col, columns.Set):
klass = SetUpdateClause
elif isinstance(col, columns.Map):
klass = MapUpdateClause
else:
raise RuntimeError
us.add_assignment_clause(
klass(col_name, col.to_database(val), operation=col_op))
else:
us.add_assignment_clause(
AssignmentClause(col_name, col.to_database(val)))
if us.assignments:
self._execute(us)
if nulled_columns:
ds = DeleteStatement(self.column_family_name,
fields=nulled_columns,
where=self._where)
self._execute(ds)
def update(self):
"""
updates a row.
This is a blind update call.
All validation and cleaning needs to happen
prior to calling this.
"""
if self.instance is None:
raise CQLEngineException("DML Query intance attribute is None")
assert type(self.instance) == self.model
null_clustering_key = False if len(
self.instance._clustering_keys) == 0 else True
static_changed_only = True
statement = UpdateStatement(self.column_family_name,
ttl=self._ttl,
timestamp=self._timestamp,
transactions=self._transaction)
for name, col in self.instance._clustering_keys.items():
null_clustering_key = null_clustering_key and col._val_is_null(
getattr(self.instance, name, None))
# get defined fields and their column names
for name, col in self.model._columns.items():
# if clustering key is null, don't include non static columns
if null_clustering_key and not col.static and not col.partition_key:
continue
if not col.is_primary_key:
val = getattr(self.instance, name, None)
val_mgr = self.instance._values[name]
# don't update something that is null
if val is None:
continue
# don't update something if it hasn't changed
if not val_mgr.changed and not isinstance(
col, columns.Counter):
continue
static_changed_only = static_changed_only and col.static
if isinstance(col,
(columns.BaseContainerColumn, columns.Counter)):
# get appropriate clause
if isinstance(col, columns.List):
klass = ListUpdateClause
elif isinstance(col, columns.Map):
klass = MapUpdateClause
elif isinstance(col, columns.Set):
klass = SetUpdateClause
elif isinstance(col, columns.Counter):
klass = CounterUpdateClause
else:
raise RuntimeError
# do the stuff
clause = klass(col.db_field_name,
val,
previous=val_mgr.previous_value,
column=col)
if clause.get_context_size() > 0:
statement.add_assignment_clause(clause)
else:
statement.add_assignment_clause(
AssignmentClause(col.db_field_name,
col.to_database(val)))
if statement.get_context_size() > 0 or self.instance._has_counter:
for name, col in self.model._primary_keys.items():
# only include clustering key if clustering key is not null, and non static columns are changed to avoid cql error
if (null_clustering_key
or static_changed_only) and (not col.partition_key):
continue
statement.add_where_clause(
WhereClause(col.db_field_name, EqualsOperator(),
col.to_database(getattr(self.instance, name))))
self._execute(statement)
if not null_clustering_key:
self._delete_null_columns()
def test_insert_tuple(self):
ac = AssignmentClause('a', 'b')
ac.set_context_id(10)
self.assertEqual(ac.insert_tuple(), ('a', 10))
def test_insert_tuple(self):
ac = AssignmentClause('a', 'b')
ac.set_context_id(10)
self.assertEqual(ac.insert_tuple(), ('a', 10))
def assignment_clauses_from_data(data):
assignment_clauses = []
for k, v in data.items():
assignment_clauses.append(AssignmentClause(k, v))
return assignment_clauses
def test_additional_rendering(self):
ist = InsertStatement('table', ttl=60)
ist.add_assignment_clause(AssignmentClause('a', 'b'))
ist.add_assignment_clause(AssignmentClause('c', 'd'))
self.assertIn('USING TTL 60', six.text_type(ist))
def test_insert_tuple(self):
ac = AssignmentClause("a", "b")
ac.set_context_id(10)
self.assertEqual(ac.insert_tuple(), ("a", 10))
