Scylla and Apache Cassandra Compatibility¶

Latest update: Scylla 4.0

Scylla is a drop-in replacement for Apache Cassandra 3.11, supporting both the data format (SSTable) and all relevant external interfaces, with many features from more advanced Apache Cassandra releases. The following page detailed the level of support for each interface. For more on Cassandra features which are not available yet see here

Note

This table includes Apache Cassandra features and the corresponding Scylla Open Source status. It does not include Scylla Enterprise features or Scylla Open Source features with no match in Apache Cassandra. More on Scylla Features

For all tables below, the following convention is used:

✕ - Not Available in Scylla
NC - Available in Scylla, but not compatible with Apache Cassandra
✔ - Available and compatible with Apache Cassandra

Interfaces¶

Apache Cassandra	Version	Comments
CQL	CQL spec 3.4.0, Native protocol v4 (C* 3.11)	More below
Thrift	Compatible with Cassandra 2.1
SSTable format	3.11(mc), 2.2(la), 2.1.8 (ka)
JMX	3.11	More Below
Configuration (cassandra.yaml)	3.11
Log	NC
Gossip and internal streaming	NC
SSL	NC

Supported Tools¶

(based on Apache Cassandra 3.11 release)

Nodetool Reference - Scylla commands for managing Scylla node or cluster using the command-line nodetool utility.
CQLSh - the CQL shell.
REST - Scylla REST/HTTP Admin API.
Tracing - a ScyllaDB tool for debugging and analyzing internal flows in the server.
SSTableloader - Bulk load the sstables found in the directory to a Scylla cluster
cassandra-stress A tool for benchmarking and load testing a Scylla and Cassandra clusters.
SSTabledump - Scylla 3.0, Scylla Enterprise 2019.1 and newer versions
SSTable2JSON - Scylla 2.3 and older
sstablelevelreset - Reset level to 0 on a selected set of SSTables that use LeveledCompactionStrategy (LCS).
sstablemetadata - Prints metadata about a specified SSTable.
sstablerepairedset - Mark specific SSTables as repaired or unrepaired.
configuration_encryptor - encrypt at rest sensitive scylla configuration entries using system key.
local_file_key_generator - Generate a local file (system) key for encryption at rest, with the provided length, Key algorithm, Algorithm block mode and Algorithm padding method.
scyllatop - A terminal base top-like tool for scylladb collectd/prometheus metrics.
scylla_dev_mode_setup - run Scylla in Developer Mode.

Run each tool with -h, --help for full options description.

Features¶

Consistency Level (read and write)¶

Options	Support
Any (Write Only)	✔
One	✔
Two	✔
Three	✔
Quorum	✔
All	✔
Local One	✔
Local Quorum	✔
Each Quorum (Write Only)	✔
SERIAL	✔ ^*
LOCAL_SERIAL	✔^*

^* From Scylla 4.0. See Scylla LWT

Snitches¶

Options	Support
SimpleSnitch	✔
RackInferringSnitch	✔
PropertyFileSnitch	✕
GossipingPropertyFileSnitch	✔
Dynamic snitching	✕
EC2Snitch	✔
EC2MultiRegionSnitch	✔
GoogleCloudSnitch	✔
CloudstackSnitch	✕

Partioners¶

Options	Support
Murmur3Partitioner (default)	✔
RandomPartitioner	✕ ^*
OrderPreservingPartitioner	✕
ByteOrderedPartitioner	✕ ^*
CollatingOrderPreservingPartitioner	✕

^* Removed in Scylla 4.0

Protocol Options¶

Options	Support
Encryption	✔
Authentication	✔
Compression (see below)	✔

Compression¶

Options	Support
CQL Compression	✔
LZ4	✔
Snappy	✔
Node to Node Compression	✔
Client to Node Compression	✔

Backup and Restore¶

Options	Support
Snapshot	✔
Incremental backup	✔
Restore	✔

Repair and Consistency¶

Options	Support
Nodetool Repair	✔
Incremental Repair	✕
Hinted Handoff	✔
Lightweight transactions	✔^*

^* From Scylla 4.0. See Scylla LWT

Replica Replacement Strategy¶

Options	Support
SimpleStrategy	✔
NetworkTopologyStrategy	✔

Security¶

Options	Support
Role Based Access Control (RBAC)	✔

Indexing and Caching¶

Options	Support
row / key cache	✕ (More on Scylla memory and cache)
Secondary Index	✔ ^*
Materialized Views	✔^*

^* In Scylla Open Source and Scylla Enterprise from 2019.1

Additional Features¶

Feature	Support
Counters	✔
User Defined Types	✔
User Defined Functions	✕ ^*
Time to live (TTL)	✔
Super Column	✕
vNode Enable	✔ Default
vNode Disable	✕
Triggers	✕
Batch Requests	✔ Includes conditional updates

^* Experimental

CQL Command Compatibility¶

Create Keyspace¶

Feature	Support
DURABLE_WRITES	✔
IF NOT EXISTS	✔
WITH REPLICATION	✔ (see below)

Create Keyspace with Replication¶

Feature	Support
SimpleStrategy	✔
NetworkTopologyStrategy	✔
OldNetworkTopologyStrategy	✕

Create Table¶

Feature	Support
Primary key column	✔
Compound primary key	✔
Composite partition key	✔
Clustering order	✔
Static column	✔

Create Table Att¶

Feature	Support
bloom_filter_fp_chance	✔
caching	✕ (ignored)
comment	✔
compaction	✔
compression	✔
dclocal_read_repair_chance	✔
default_time_to_live	✔
gc_grace_seconds	✔
index_interval	✕
max_index_interval	✔
memtable_flush_period_in_ms	✕ (ignored)
min_index_interval	✔
populate_io_cache_on_flush	✕
read_repair_chance	✔
replicate_on_write	✕
speculative_retry	`ALWAYS`, `NONE`

Create Table Compaction¶

Feature	Support
SizeTieredCompactionStrategy (STCS)	✔
LeveledCompactionStrategy (LCS)	✔
DateTieredCompactionStrategy (DTCS)	✔ ^*
TimeWindowCompactionStrategy (TWCS)	✔

^* Deprecated in Scylla 4.0, use TWCS instead

Create Table Compression¶

Feature	Support
sstable_compression LZ4Compressor	✔
sstable_compression SnappyCompressor	✔
sstable_compression DeflateCompressor	✔
chunk_length_kb	✔
crc_check_chance	✕

Alter Commands¶

Feature	Support
ALTER KEYSPACE	✔
ALTER TABLE	✔
ALTER TYPE	✔
ALTER USER	✔
ALTER ROLE	✔

Data Manipulation¶

Feature	Support
BATCH	✔
INSERT	✔
Prepared Statements	✔
SELECT	✔
TRUNCATE	✔
UPDATE	✔
USE	✔

Create Commands¶

Feature	Support
CREATE TRIGGER	✕
CREATE USER	✔
CREATE ROLE	✔

Drop Commands¶

Feature	Support
DROP KEYSPACE	✔
DROP TABLE	✔
DROP TRIGGER	✕
DROP TYPE	✔
DROP USER	✔
DROP ROLE	✔

Roles and Permissions¶

Feature	Support
GRANT PERMISSIONS	✔
GRANT ROLE	✔
LIST PERMISSIONS	✔
LIST USERS	✔
LIST ROLES	✔
REVOKE PERMISSIONS	✔
REVOKE ROLE	✔

Materialized Views¶

Feature	Support
MATERIALIZED VIEW	✔
ALTER MATERIALIZED VIEW	✔
CREATE MATERIALIZED VIEW	✔
DROP MATERIALIZED VIEW	✔

Index commands¶

Feature	Support
INDEX	✔
CREATE INDEX	✔
DROP INDEX	✔

Apache®, Apache Cassandra®, Cassandra®, the Apache feather logo and the Apache Cassandra® Eye logo are either registered trademarks or trademarks of the Apache Software Foundation in the United States and/or other countries. No endorsement by The Apache Software Foundation is implied by the use of these marks.