def create_index(self,
keyspace,
column_family,
column,
value_type,
index_type=KEYS_INDEX,
index_name=None):
"""
Creates an index on a column.
This allows efficient for index usage via
:meth:`~pycassa.columnfamily.ColumnFamily.get_indexed_slices()`
`column` specifies what column to index, and `value_type` is a string
that describes that column's value's data type; see
:meth:`alter_column()` for a full description of `value_type`.
`index_type` determines how the index will be stored internally. Currently,
:const:`KEYS_INDEX` is the only option. `index_name` is an optional name
for the index.
Example Usage:
.. code-block:: python
>>> from pycassa.system_manager import *
>>> sys = SystemManager('192.168.2.10:9160')
>>> sys.create_index('Keyspace1', 'Standard1', 'birthdate', LONG_TYPE, index_name='bday_index')
>>> sys.close
"""
self._conn.set_keyspace(keyspace)
cfdef = self.get_keyspace_column_families(keyspace)[column_family]
col_name_data_type = util.extract_type_name(cfdef.comparator_type)
packed_column = util.pack(column, col_name_data_type)
if value_type.find('.') == -1:
value_type = 'org.apache.cassandra.db.marshal.%s' % value_type
coldef = ColumnDef(packed_column, value_type, index_type, index_name)
for c in cfdef.column_metadata:
if c.name == packed_column:
cfdef.column_metadata.remove(c)
break
cfdef.column_metadata.append(coldef)
self._system_update_column_family(cfdef)
def _alter_column_cfdef(self, cfdef, column, value_type):
if cfdef.column_type == 'Super':
packer = marshal.packer_for(cfdef.subcomparator_type)
else:
packer = marshal.packer_for(cfdef.comparator_type)
packed_column = packer(column)
value_type = self._qualify_type_class(value_type)
cfdef.column_metadata = cfdef.column_metadata or []
matched = False
for c in cfdef.column_metadata:
if c.name == packed_column:
c.validation_class = value_type
matched = True
break
if not matched:
cfdef.column_metadata.append(ColumnDef(packed_column, value_type, None, None))
return cfdef
def alter_column(self, keyspace, column_family, column, value_type):
"""
Sets a data type for the value of a specific column.
`value_type` is a string that determines what type the column value will be.
By default, :const:`LONG_TYPE`, :const:`INT_TYPE`,
:const:`ASCII_TYPE`, :const:`UTF8_TYPE`, :const:`TIME_UUID_TYPE`,
:const:`LEXICAL_UUID_TYPE` and :const:`BYTES_TYPE` are provided. Custom
types may be used as well by providing the class name; if the custom
comparator class is not in ``org.apache.cassandra.db.marshal``, the fully
qualified class name must be given.
For super column families, this sets the subcolumn value type for
any subcolumn named `column`, regardless of the super column name.
"""
self._conn.set_keyspace(keyspace)
cfdef = self.get_keyspace_column_families(keyspace)[column_family]
if cfdef.column_type == 'Super':
col_name_data_type = util.extract_type_name(
cfdef.subcomparator_type)
else:
col_name_data_type = util.extract_type_name(cfdef.comparator_type)
packed_column = util.pack(column, col_name_data_type)
if value_type.find('.') == -1:
value_type = 'org.apache.cassandra.db.marshal.%s' % value_type
matched = False
for c in cfdef.column_metadata:
if c.name == packed_column:
c.validation_class = value_type
matched = True
break
if not matched:
cfdef.column_metadata.append(
ColumnDef(packed_column, value_type, None, None))
self._system_update_column_family(cfdef)