本文整理汇总了Python中cassandra.cqlengine.statements.DeleteStatement类的典型用法代码示例。如果您正苦于以下问题：Python DeleteStatement类的具体用法？Python DeleteStatement怎么用？Python DeleteStatement使用的例子？那么恭喜您, 这里精选的类代码示例或许可以为您提供帮助。
在下文中一共展示了DeleteStatement类的9个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的Python代码示例。
示例1: delete
def delete(self):
""" Deletes one instance """
if self.instance is None:
raise CQLEngineException("DML Query instance attribute is None")
ds = DeleteStatement(self.column_family_name, timestamp=self._timestamp, conditionals=self._conditional, if_exists=self._if_exists)
for name, col in self.model._primary_keys.items():
val = getattr(self.instance, name)
if val is None and not col.parition_key:
continue
ds.add_where(col, EqualsOperator(), val)
self._execute(ds)示例2: delete
def delete(self):
""" Deletes one instance """
if self.instance is None:
raise CQLEngineException("DML Query instance attribute is None")
ds = DeleteStatement(self.column_family_name, timestamp=self._timestamp)
for name, col in self.model._primary_keys.items():
if (not col.partition_key) and (getattr(self.instance, name) is None):
continue
ds.add_where_clause(
WhereClause(col.db_field_name, EqualsOperator(), col.to_database(getattr(self.instance, name)))
)
self._execute(ds)示例3: test_context_update
def test_context_update(self):
ds = DeleteStatement('table', None)
ds.add_field(MapDeleteClause('d', {1: 2}, {1: 2, 3: 4}))
ds.add_where_clause(WhereClause('a', EqualsOperator(), 'b'))
ds.update_context_id(7)
self.assertEqual(six.text_type(ds), 'DELETE "d"[%(8)s] FROM table WHERE "a" = %(7)s')
self.assertEqual(ds.get_context(), {'7': 'b', '8': 3})示例4: _delete_null_columns
def _delete_null_columns(self):
"""
executes a delete query to remove columns that have changed to null
"""
ds = DeleteStatement(self.column_family_name, if_exists=self._if_exists)
deleted_fields = False
for _, v in self.instance._values.items():
col = v.column
if v.deleted:
ds.add_field(col.db_field_name)
deleted_fields = True
elif isinstance(col, columns.Map):
uc = MapDeleteClause(col.db_field_name, v.value, v.previous_value)
if uc.get_context_size() > 0:
ds.add_field(uc)
deleted_fields = True
if deleted_fields:
for name, col in self.model._primary_keys.items():
ds.add_where_clause(WhereClause(
col.db_field_name,
EqualsOperator(),
col.to_database(getattr(self.instance, name))
))
self._execute(ds)示例5: test_range_deletion_rendering
def test_range_deletion_rendering(self):
ds = DeleteStatement('table', None)
ds.add_where_clause(WhereClause('a', EqualsOperator(), 'b'))
ds.add_where_clause(WhereClause('created_at', GreaterThanOrEqualOperator(), '0'))
ds.add_where_clause(WhereClause('created_at', LessThanOrEqualOperator(), '10'))
self.assertEqual(six.text_type(ds), 'DELETE FROM table WHERE "a" = %(0)s AND "created_at" >= %(1)s AND "created_at" <= %(2)s', six.text_type(ds))
ds = DeleteStatement('table', None)
ds.add_where_clause(WhereClause('a', EqualsOperator(), 'b'))
ds.add_where_clause(WhereClause('created_at', InOperator(), ['0', '10', '20']))
self.assertEqual(six.text_type(ds), 'DELETE FROM table WHERE "a" = %(0)s AND "created_at" IN %(1)s', six.text_type(ds))示例6: test_context
def test_context(self):
ds = DeleteStatement('table', None)
ds.add_where_clause(WhereClause('a', EqualsOperator(), 'b'))
self.assertEqual(ds.get_context(), {'0': 'b'})示例7: test_where_clause_rendering
def test_where_clause_rendering(self):
ds = DeleteStatement('table', None)
ds.add_where_clause(WhereClause('a', EqualsOperator(), 'b'))
self.assertEqual(six.text_type(ds), 'DELETE FROM table WHERE "a" = %(0)s', six.text_type(ds))示例8: test_range_deletion_rendering
def test_range_deletion_rendering(self):
ds = DeleteStatement('table', None)
ds.add_where(Column(db_field='a'), EqualsOperator(), 'b')
ds.add_where(Column(db_field='created_at'), GreaterThanOrEqualOperator(), '0')
ds.add_where(Column(db_field='created_at'), LessThanOrEqualOperator(), '10')
self.assertEqual(six.text_type(ds), 'DELETE FROM table WHERE "a" = %(0)s AND "created_at" >= %(1)s AND "created_at" <= %(2)s', six.text_type(ds))
ds = DeleteStatement('table', None)
ds.add_where(Column(db_field='a'), EqualsOperator(), 'b')
ds.add_where(Column(db_field='created_at'), InOperator(), ['0', '10', '20'])
self.assertEqual(six.text_type(ds), 'DELETE FROM table WHERE "a" = %(0)s AND "created_at" IN %(1)s', six.text_type(ds))
ds = DeleteStatement('table', None)
ds.add_where(Column(db_field='a'), NotEqualsOperator(), 'b')
self.assertEqual(six.text_type(ds), 'DELETE FROM table WHERE "a" != %(0)s', six.text_type(ds))示例9: test_context
def test_context(self):
ds = DeleteStatement('table', None)
ds.add_where(Column(db_field='a'), EqualsOperator(), 'b')
self.assertEqual(ds.get_context(), {'0': 'b'})