openstack/deb-python-cassandra-driver
Code Issues Proposed changes

cqle: update docs for new __options__ model attribute

Browse Source
This commit is contained in:
Adam Holmberg
2015-09-30 14:15:51 -05:00
parent 1048f33604
commit 75ddc51461
1 changed files with 24 additions and 72 deletions
Download Patch File Download Diff File Expand all files Collapse all files

96
docs/api/cassandra/cqlengine/models.rst
View File

@@ -20,8 +20,8 @@ Model
person.first_name #returns 'Blake'
person.last_name #returns 'Eggleston'
*Model attributes define how the model maps to tables in the database. These are class variables that should be set
when defining Model deriviatives.*
Model attributes define how the model maps to tables in the database. These are class variables that should be set
when defining Model deriviatives.
.. autoattribute:: __abstract__
:annotation: = False
@@ -39,97 +39,49 @@ Model
See :ref:`model_inheritance` for usage examples.
*Each table can have its own set of configuration options.
These can be specified on a model with the following attributes:*
Each table can have its own set of configuration options, including compaction. Unspecified, these default to sensible values in
the server. To override defaults, set options using the model ``__options__`` attribute, which allows options specified a dict.
When a table is synced, it will be altered to match the options set on your table.
This means that if you are changing settings manually they will be changed back on resync.
Do not use the options settings of cqlengine if you want to manage your compaction settings manually.
See the `list of supported table properties for more information
<http://www.datastax.com/documentation/cql/3.1/cql/cql_reference/tabProp.html>`_.
.. attribute:: __bloom_filter_fp_chance
.. attribute:: __caching__
.. attribute:: __comment__
.. attribute:: __dclocal_read_repair_chance__
.. attribute:: __default_time_to_live__
.. attribute:: __gc_grace_seconds__
.. attribute:: __index_interval__
.. attribute:: __memtable_flush_period_in_ms__
.. attribute:: __populate_io_cache_on_flush__
.. attribute:: __read_repair_chance__
.. attribute:: __replicate_on_write__
*Model presently supports specifying compaction options via class attributes.
cqlengine will only use your compaction options if you have a strategy set.
When a table is synced, it will be altered to match the compaction options set on your table.
This means that if you are changing settings manually they will be changed back on resync.*
*Do not use the compaction settings of cqlengine if you want to manage your compaction settings manually.*
*cqlengine supports all compaction options as of Cassandra 1.2.8.*
**These attibutes will likely be replaced by a single options string in a future version, and are therefore deprecated.**
.. attribute:: __compaction_bucket_high__
:annotation: Deprecated
.. attribute:: __compaction_bucket_low__
:annotation: Deprecated
.. attribute:: __compaction_max_compaction_threshold__
:annotation: Deprecated
.. attribute:: __compaction_min_compaction_threshold__
:annotation: Deprecated
.. attribute:: __compaction_min_sstable_size__
:annotation: Deprecated
.. attribute:: __compaction_sstable_size_in_mb__
:annotation: Deprecated
.. attribute:: __compaction_tombstone_compaction_interval__
:annotation: Deprecated
.. attribute:: __compaction_tombstone_threshold__
:annotation: Deprecated
.. attribute:: __options__
For example:
.. code-block:: python
class User(Model):
__compaction__ = cqlengine.LeveledCompactionStrategy
__compaction_sstable_size_in_mb__ = 64
__compaction_tombstone_threshold__ = .2
__options__ = {'compaction': {'class': 'LeveledCompactionStrategy',
'sstable_size_in_mb': '64',
'tombstone_threshold': '.2'},
'read_repair_chance': '0.5',
'comment': 'User data stored here'}
user_id = columns.UUID(primary_key=True)
name = columns.Text()
or for SizeTieredCompaction:
or :
.. code-block:: python
class TimeData(Model):
__compaction__ = SizeTieredCompactionStrategy
__compaction_bucket_low__ = .3
__compaction_bucket_high__ = 2
__compaction_min_threshold__ = 2
__compaction_max_threshold__ = 64
__compaction_tombstone_compaction_interval__ = 86400
__options__ = {'compaction': {'class': 'SizeTieredCompactionStrategy',
'bucket_low': '.3',
'bucket_high': '2',
'min_threshold': '2',
'max_threshold': '64',
'tombstone_compaction_interval': '86400'},
'gc_grace_seconds': '0'}
Tables may use `LeveledCompactionStrategy` or `SizeTieredCompactionStrategy`. Both options are available in the top level cqlengine module. To reiterate, you will need to set your `__compaction__` option explicitly in order for cqlengine to handle any of your settings.
*The base methods allow creating, storing, and querying modeled objects.*
The base methods allow creating, storing, and querying modeled objects.
.. automethod:: create