sstabledowngrade

Downgrades the SSTables in the given table or snapshot to the version of OSS Apache Cassandra that is compatible with the current version of DSE while the DSE node is offline.

Downgrades the SSTables in the given table or snapshot to the version of OSS Apache Cassandra™ that is compatible with the current version of DSE while the DSE node is offline.

Important: The sstabledowngrade command cannot be used to downgrade system tables or downgrade DSE versions.

Restriction: Stop DataStax Enterprise before you run this command.

The default location of this SSTable tool depends on the type of installation:

Package installations: /usr/bin/
Tarball installations: installation_location/resources/cassandra/bin

Synopsis

sstabledowngrade
[--debug] 
[-h | --help] 
[[-k | --keep-source] | [--keep-generation]] 
[-b | --backups]  
[-o | --output-dir output-dir] 
[--schema schema-file [--schema schema-file2 ... ]]
[-t | --throughput rate-limit] 
[--temp-storage tmp-dir]
keyspace_name 
table_name
[snapshot_name]

SSTable versions

For details on SSTable versions and compatibility, see DataStax Enterprise, Apache Cassandra, CQL, and SSTable compatibility.

Definition

The short form and long form parameters are comma-separated.

Command arguments

--debug

Display stack traces.

-h, --help

Display the usage and listing of the commands.

-k, --keep-source

Do not delete the source SSTables. Do not use with the --keep-generation option.

-b, --backups

Rewrite incremental backups for the given table. May not be combined with the snapshot_name option.

--keep-generation

Keep the generated SSTables. Do not use with the --keep-source option.

-o, --output-dir

Rewritten files are placed in output-dir/keyspace-name/table-name-and-id.

--schema

Allows upgrading and downgrading SSTables using the schema of the table in a CQL file containing the DDL statements to re-create the schema. Must be a DDL file that allows the recreation of the table including dropped columns. Repeat the option to specify multiple DDL schema files.

Important: Always use the schema.cql from a snapshot of the table so that the DDL has all of the information omitted by DESCRIBE TABLE, including dropped columns.

-t, --throughput

Set to limit the maximum disk read rate in MB/s.

--temp-storage

When used with --schema, specifies location of temporary data. Directory and contents are deleted when the tool terminates. Directory must not be shared with other tools and must be empty. If not specified the default directory is /tmp.

keyspace_name

Keyspace name. Required.

table_name

Table name. Required.

snapshot_name

Snapshot name.

Rewrites only the specified snapshot.
Replaces files in the given snapshot and breaks any hard links to live SSTables.
Required when before attempting to restore a snapshot taken in a different DSE version than the one that is currently running.

Examples

Downgrade events table in the cycling keyspace

Restriction: Stop DataStax Enterprise before you run this command.

sstabledowngrade cycling events

Found 1 sstables to rewrite.
Rewriting TrieIndexSSTableReader(path='/var/lib/cassandra/data/cycling/events-2118bc7054af11e987feb76774f7ab56/aa-1-bti-Data.db') to BIG/mc.
Rewrite of TrieIndexSSTableReader(path='/var/lib/cassandra/data/cycling/events-2118bc7054af11e987feb76774f7ab56/aa-1-bti-Data.db') to BIG/mc complete.