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ScyllaDB Python Driver is available under the Apache v2 License. ScyllaDB Python Driver is a fork of DataStax Python Driver. See Copyright here.
cqlengine is the Cassandra CQL 3 Object Mapper packaged with this driver
For migrating projects from legacy cqlengine, to the integrated product
Examples defining models, and mapping them to tables
Overview of query sets and filtering
Working with batch mutations
Working with multiple sessions
Index of API documentation
High-level examples in Celery and uWSGI
import uuid
from cassandra.cqlengine import columns
from cassandra.cqlengine import connection
from datetime import datetime
from cassandra.cqlengine.management import sync_table
from cassandra.cqlengine.models import Model
#first, define a model
class ExampleModel(Model):
example_id = columns.UUID(primary_key=True, default=uuid.uuid4)
example_type = columns.Integer(index=True)
created_at = columns.DateTime()
description = columns.Text(required=False)
#next, setup the connection to your cassandra server(s)...
# see http://datastax.github.io/python-driver/api/cassandra/cluster.html for options
# the list of hosts will be passed to create a Cluster() instance
connection.setup(['127.0.0.1'], "cqlengine", protocol_version=3)
#...and create your CQL table
>>> sync_table(ExampleModel)
#now we can create some rows:
>>> em1 = ExampleModel.create(example_type=0, description="example1", created_at=datetime.now())
>>> em2 = ExampleModel.create(example_type=0, description="example2", created_at=datetime.now())
>>> em3 = ExampleModel.create(example_type=0, description="example3", created_at=datetime.now())
>>> em4 = ExampleModel.create(example_type=0, description="example4", created_at=datetime.now())
>>> em5 = ExampleModel.create(example_type=1, description="example5", created_at=datetime.now())
>>> em6 = ExampleModel.create(example_type=1, description="example6", created_at=datetime.now())
>>> em7 = ExampleModel.create(example_type=1, description="example7", created_at=datetime.now())
>>> em8 = ExampleModel.create(example_type=1, description="example8", created_at=datetime.now())
#and now we can run some queries against our table
>>> ExampleModel.objects.count()
8
>>> q = ExampleModel.objects(example_type=1)
>>> q.count()
4
>>> for instance in q:
>>> print instance.description
example5
example6
example7
example8
#here we are applying additional filtering to an existing query
#query objects are immutable, so calling filter returns a new
#query object
>>> q2 = q.filter(example_id=em5.example_id)
>>> q2.count()
1
>>> for instance in q2:
>>> print instance.description
example5
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ScyllaDB Python Driver is available under the Apache v2 License. ScyllaDB Python Driver is a fork of DataStax Python Driver. See Copyright here.
cassandra
- Exceptions and Enumscassandra.cluster
- Clusters and Sessionscassandra.policies
- Load balancing and Failure Handling Policiescassandra.auth
- Authenticationcassandra.graph
- Graph Statements, Options, and Row Factoriescassandra.metadata
- Schema and Ring Topologycassandra.metrics
- Performance Metricscassandra.query
- Prepared Statements, Batch Statements, Tracing, and Row Factoriescassandra.pool
- Hosts and Connection Poolscassandra.protocol
- Protocol Featurescassandra.encoder
- Encoders for non-prepared Statementscassandra.decoder
- Data Return Formatscassandra.concurrent
- Utilities for Concurrent Statement Executioncassandra.connection
- Low Level Connection Infocassandra.util
- Utilitiescassandra.timestamps
- Timestamp Generationcassandra.io.asyncioreactor
- asyncio
Event Loopcassandra.io.asyncorereactor
- asyncore
Event Loopcassandra.io.eventletreactor
- eventlet
-compatible Connectioncassandra.io.libevreactor
- libev
Event Loopcassandra.io.geventreactor
- gevent
-compatible Event Loopcassandra.io.twistedreactor
- Twisted Event Loopcassandra.cqlengine.models
- Table models for object mappingcassandra.cqlengine.columns
- Column types for object mapping modelscassandra.cqlengine.query
- Query and filter model objectscassandra.cqlengine.connection
- Connection management for cqlenginecassandra.cqlengine.management
- Schema management for cqlenginecassandra.cqlengine.usertype
- Model classes for User Defined Typescassandra.datastax.graph
- Graph Statements, Options, and Row Factoriescassandra.datastax.graph.fluent
cassandra.datastax.graph.fluent.query
cassandra.datastax.graph.fluent.predicates
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