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Caution
You're viewing documentation for a previous version of ScyllaDB Enterprise. Switch to the latest stable version.
cqlsh is a command line shell for interacting with ScyllaDB through CQL
(the Cassandra Query Language). It is shipped with every ScyllaDB package
and can be found in the bin/
directory. In addition, it is available on
Docker Hub and in
the Python Package Index (PyPI).
cqlsh utilizes the Python native protocol driver and connects to the single node specified on the command line.
See the scylla-cqlsh repository on GitHub for usage examples.
cqlsh is compatible with Python 3.8 - Python 3.11.
A given version of cqlsh is only guaranteed to work with the version of ScyllaDB that it was released with. cqlsh may work with older or newer versions of ScyllaDB without any guarantees.
cqlsh ships with all essential dependencies. However, there are some optional dependencies that can be installed to improve the capabilities of cqlsh.
By default, cqlsh displays all timestamps with a UTC timezone. To support display of timestamps with another timezone,
the pytz library must be installed. See the timezone
option in cqlshrc for
specifying a timezone to use.
The performance of cqlsh’s COPY
operations can be improved by installing cython. This will
compile the python modules that are central to the performance of COPY
.
The cqlshrc
file holds configuration options for cqlsh. By default, this is in the user’s home directory:
~/.cassandra/cqlsh
, but a custom location can be specified with the --cqlshrc
option.
Example config values and documentation can be found in the conf/cqlshrc.sample
file of a tarball installation. You
can also view the latest version of cqlshrc online.
Usage:
cqlsh [options] [host [port]]
Options:
-C
--color
Force color output
--no-color
Disable color output
--browser
Specify the browser to use for displaying cqlsh help. This can be one of the supported browser names (e.g. firefox
) or a browser path followed by %s
(e.g.
/usr/bin/google-chrome-stable %s
).
--ssl
Use SSL when connecting to ScyllaDB.
-u
--user
Username to authenticate against ScyllaDB.
-p
--password
The password to authenticate against ScyllaDB, which should
be used in conjunction with --user
-k
--keyspace
Keyspace to authenticate to should be used in conjunction
with --user
-f
--file
Execute commands from the given file, then exit
--debug
Print additional debugging information
--encoding
Specify a non-default encoding for output (defaults to UTF-8)
--cqlshrc
Specify a non-default location for the cqlshrc
file
-e
--execute
Execute the given statement, then exit
--connect-timeout
Specify the connection timeout in seconds (defaults to 2s)
--request-timeout
Specify the request timeout in seconds (defaults to 10s)
-t
--tty
Force tty mode (command prompt)
In addition to supporting regular CQL statements, cqlsh also supports a number of special commands that are not part of CQL. These are detailed below.
Usage: CONSISTENCY <consistency level>
Sets the consistency level for operations to follow. Valid arguments include:
- ANY
- ONE
- TWO
- THREE
- QUORUM
- ALL
- LOCAL_QUORUM
- LOCAL_ONE
- SERIAL
- LOCAL_SERIAL
Usage: SERIAL CONSISTENCY <consistency level>
Sets the serial consistency level for operations to follow. Valid arguments include:
SERIAL
LOCAL_SERIAL
The serial consistency level is only used by conditional updates (INSERT
, UPDATE
, and DELETE
with an IF
condition). For those, the serial consistency level defines the consistency level of the serial phase (or “paxos” phase)
while the normal consistency level defines the consistency for the “learn” phase, i.e. what type of reads will be
guaranteed to see the update right away. For example, if a conditional write has a consistency level of QUORUM
(and
is successful), then a QUORUM
read is guaranteed to see that write. However, if the regular consistency level of that
write is ANY
, then only a read with a consistency level of SERIAL
is guaranteed to see it (even a read with
consistency ALL
is not guaranteed to be enough).
This command is useful if you want to check which Cassandra version is compatible with your ScyllaDB version. Note that the two standards are not 100% identical and this command is simply a comparison tool.
If you want to display your current ScyllaDB version, refer to Check your current version of Scylla.
The display shows:
The cqlsh tool version that you’re using
The Apache Cassandra version that your version of ScyllaDB is most compatible with
The CQL protocol standard that your version of ScyllaDB is most compatible with
The native protocol standard that your version of ScyllaDB is most compatible with
Example:
cqlsh> SHOW VERSION
Returns:
[cqlsh 5.0.1 | Cassandra 3.0.8 | CQL spec 3.3.1 | Native protocol v4]
Prints the IP address and port of the ScyllaDB node that cqlsh is connected to in addition to the cluster name.
Example:
cqlsh> SHOW HOST
Returns:
Connected to Prod_Cluster at 192.0.0.1:9042.
Pretty prints a specific tracing session.
Usage: SHOW SESSION <session id>
Example usage:
cqlsh> SHOW SESSION 95ac6470-327e-11e6-beca-dfb660d92ad8
Returns:
Tracing session: 95ac6470-327e-11e6-beca-dfb660d92ad8
activity | timestamp | source | source_elapsed | client
-----------------------------------------------------------+----------------------------+-----------+----------------+-----------
Execute CQL3 query | 2016-06-14 17:23:13.979000 | 127.0.0.1 | 0 | 127.0.0.1
Parsing SELECT * FROM system.local; [SharedPool-Worker-1] | 2016-06-14 17:23:13.982000 | 127.0.0.1 | 3843 | 127.0.0.1
...
Reads the contents of a file and executes each line as a CQL statement or special cqlsh command.
Usage: SOURCE <string filename>
Example usage:
cqlsh> SOURCE '/home/thobbs/commands.cql'
Begins capturing command output and appending it to a specified file. Output will not be shown at the console while it is captured.
Usage:
CAPTURE '<file>';
CAPTURE OFF;
CAPTURE;
That is, the path to the file to be appended to must be given inside a string literal. The path is interpreted relative
to the current working directory. The tilde shorthand notation ('~/mydir'
) is supported for referring to $HOME
.
Only query result output is captured. Errors and output from cqlsh-only commands will still be shown in the cqlsh session.
To stop capturing output and show it in the cqlsh session again, use CAPTURE OFF
.
To inspect the current capture configuration, use CAPTURE
with no arguments.
Gives information about cqlsh commands. To see available topics, enter HELP
without any arguments. To see help on a
topic, use HELP <topic>
. Also, see the --browser
argument for controlling what browser is used to display help.
Enables or disables tracing for queries. When tracing is enabled, once a query completes, a trace of the events during the query will be printed.
Usage:
TRACING ON
TRACING OFF
Enables paging, disables paging, or sets the page size for read queries. When paging is enabled, only one page of data will be fetched at a time, and a prompt will appear to fetch the next page. Generally, it’s a good idea to leave paging enabled in an interactive session to avoid fetching and printing large amounts of data at once.
Usage:
PAGING ON
PAGING OFF
PAGING <page size in rows>
Enables or disables vertical printing of rows. Enabling EXPAND
is useful when many columns are fetched, or the
contents of a single column are large.
Usage:
EXPAND ON
EXPAND OFF
Authenticate as a specified ScyllaDB user for the current session.
Usage:
LOGIN <username> [<password>]
Ends the current session and terminates the cqlsh process.
Usage:
EXIT
QUIT
Clears the console.
Usage:
CLEAR
CLS
Prints a description (typically a series of DDL statements) of a schema element or the cluster. This is useful for dumping all or portions of the schema.
DESCRIBE CLUSTER
DESCRIBE SCHEMA
DESCRIBE KEYSPACES
DESCRIBE KEYSPACE <keyspace name>
DESCRIBE TABLES
DESCRIBE TABLE <table name>
DESCRIBE MATERIALIZED VIEW <view name>
DESCRIBE TYPES
DESCRIBE TYPE <type name>
DESCRIBE FUNCTIONS
DESCRIBE FUNCTION <function name>
DESCRIBE AGGREGATES
DESCRIBE AGGREGATE <aggregate function name>
In any of the commands, DESC
may be used in place of DESCRIBE
.
DESCRIBE <name>
. This will look for the objectin a specific order: keyspace, table, view, index, user-defined type, user-defined function, user-defined aggregate.
The DESCRIBE CLUSTER
command prints the cluster name and partitioner:
cqlsh> DESCRIBE CLUSTER
Cluster: Test Cluster
Partitioner: Murmur3Partitioner
The DESCRIBE SCHEMA
command prints the DDL statements needed to recreate the entire schema. This is especially
useful for dumping the schema in order to clone a cluster or restore from a backup.
Copies data from a table to a CSV file.
COPY <table name> [(<column>, ...)] TO <file name> WITH <copy option> [AND <copy option> ...]
If no columns are specified, all columns from the table will be copied to the CSV file. A subset of columns to copy may be specified by adding a comma-separated list of column names surrounded by parenthesis after the table name.
The <file name>
should be a string literal (with single quotes) representing a path to the destination file. The
file name can also contain the special value STDOUT
(without single quotes) print the CSV to STDOUT.
See Shared COPY Options for options that apply to both COPY TO
and COPY FROM
.
MAXREQUESTS
The maximum number token ranges to fetch simultaneously. Defaults to 6.
PAGESIZE
The number of rows to fetch in a single page. Defaults to 1000.
PAGETIMEOUT
By default, the page timeout is 10 seconds per 1000 entries in the page size or 10 seconds if pagesize is smaller.
BEGINTOKEN
, ENDTOKEN
Token range to export. Defaults to exporting the full ring.
MAXOUTPUTSIZE
The maximum size of the output file measured in number of lines; beyond this maximum the output file will be split into segments. -1 means unlimited, and is the default.
ENCODING
The encoding used for characters. Defaults to utf8
.
Copies data from a CSV file to table.
COPY <table name> [(<column>, ...)] FROM <file name> WITH <copy option> [AND <copy option> ...]
If no columns are specified, all columns from the CSV file will be copied to the table. A subset of columns to copy may be specified by adding a comma-separated list of column names surrounded by parenthesis after the table name.
The <file name>
should be a string literal (with single quotes) representing a path to the
source file. The file name can also contain the special value``STDIN`` (without single quotes)
to read the CSV data from STDIN.
See Shared COPY Options for options that apply to both COPY TO
and COPY FROM
.
INGESTRATE
The maximum number of rows to process per second. Defaults to 100000.
MAXROWS
The maximum number of rows to import. -1 means unlimited, and is the default.
SKIPROWS
A number of initial rows to skip. Defaults to 0.
SKIPCOLS
A comma-separated list of column names to ignore. By default, no columns are skipped.
MAXPARSEERRORS
The maximum global number of parsing errors to ignore. -1 means unlimited, and is the default.
MAXINSERTERRORS
The maximum global number of insert errors to ignore. -1 means unlimited. The default is 1000.
ERRFILE
=A file to store all rows that could not be imported. By default, this is import_<ks>_<table>.err
where <ks>
is
your keyspace and <table>
is your table name.
MAXBATCHSIZE
The max number of rows inserted in a single batch. Defaults to 20.
MINBATCHSIZE
The min number of rows inserted in a single batch. Defaults to 2.
CHUNKSIZE
The number of rows that are passed to child worker processes from the main process at a time. Defaults to 1000.
Options that are common to both COPY TO
and COPY FROM
.
NULLVAL
The string placeholder for null values. Defaults to null
.
HEADER
For COPY TO
, controls whether the first line in the CSV output file will contain the column names. For COPY FROM,
specifies whether the first line in the CSV input file contains column names. Defaults to false
.
DECIMALSEP
The character that is used as the decimal point separator. Defaults to .
.
THOUSANDSSEP
The character that is used to separate thousands. Defaults to the empty string.
BOOLSTYlE
The string literal format for boolean values. By default this is True, False
.
NUMPROCESSES
The number of child worker processes to create for COPY
tasks. Defaults to a max of 4 for COPY FROM
and 16
for COPY TO
. However, at most (num_cores - 1), processes will be created.
MAXATTEMPTS
The maximum number of failed attempts to fetch a range of data (when using COPY TO
) or insert a chunk of data
(when using COPY FROM
) before giving up. Defaults to 5.
REPORTFREQUENCY
How often status updates are refreshed in seconds. By default, this is 0.25 seconds.
RATEFILE
An optional file to export rate statistics to. By default, this is disabled and statistics are not exported to a file.
See also:
CQLSH lesson on Scylla University
Copyright
© 2016, The Apache Software Foundation.
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.
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