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 (all versions)	3.11(mc / md ), 2.2(la), 2.1.8 (ka)	md format is supported in Scylla 4.3, 2021.1.0 and later
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

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