cassandra命令行操作

查看cqlsh命令帮助

root@sitewhere-cassandra-0:/# cqlsh --help
Usage: cqlsh.py [options] [host [port]]

CQL Shell for Apache Cassandra

Options:
  --version             show program's version number and exit
  -h, --help            show this help message and exit
  -C, --color           Always use color output
  --no-color            Never use color output
  --browser=BROWSER     The browser to use to display CQL help, where BROWSER
                        can be:
                        - one of the supported browsers in
                        https://docs.python.org/2/library/webbrowser.html.
                        - browser path followed by %s, example: /usr/bin
                        /google-chrome-stable %s
  --ssl                 Use SSL
  --no_compact          No Compact
  -u USERNAME, --username=USERNAME
                        Authenticate as user.
  -p PASSWORD, --password=PASSWORD
                        Authenticate using password.
  -k KEYSPACE, --keyspace=KEYSPACE
                        Authenticate to the given keyspace.
  -f FILE, --file=FILE  Execute commands from FILE, then exit
  --debug               Show additional debugging information
  --encoding=ENCODING   Specify a non-default encoding for output. (Default:
                        utf-8)
  --cqlshrc=CQLSHRC     Specify an alternative cqlshrc file location.
  --cqlversion=CQLVERSION
                        Specify a particular CQL version, by default the
                        highest version supported by the server will be used.
                        Examples: "3.0.3", "3.1.0"
  --protocol-version=PROTOCOL_VERSION
                        Specify a specific protcol version otherwise the
                        client will default and downgrade as necessary
  -e EXECUTE, --execute=EXECUTE
                        Execute the statement and quit.
  --connect-timeout=CONNECT_TIMEOUT
                        Specify the connection timeout in seconds (default: 5
                        seconds).
  --request-timeout=REQUEST_TIMEOUT
                        Specify the default request timeout in seconds
                        (default: 10 seconds).
  -t, --tty             Force tty mode (command prompt).
Connects to 127.0.0.1:9042 by default. These defaults can be changed by
setting $CQLSH_HOST and/or $CQLSH_PORT. When a host (and optional port number)
are given on the command line, they take precedence over any defaults.

连接数据库

root@sitewhere-cassandra-0:/# cqlsh       
Connected to cassandra at 127.0.0.1:9042.
[cqlsh 5.0.1 | Cassandra 3.11.3 | CQL spec 3.4.4 | Native protocol v4]
Use HELP for help.
cqlsh> 

查看帮助

cqlsh> help
Documented shell commands:
===========================
CAPTURE  CLS          COPY  DESCRIBE  EXPAND  LOGIN   SERIAL  SOURCE   UNICODE
CLEAR    CONSISTENCY  DESC  EXIT      HELP    PAGING  SHOW    TRACING

CQL help topics:
================
AGGREGATES               CREATE_KEYSPACE           DROP_TRIGGER      TEXT     
ALTER_KEYSPACE           CREATE_MATERIALIZED_VIEW  DROP_TYPE         TIME     
ALTER_MATERIALIZED_VIEW  CREATE_ROLE               DROP_USER         TIMESTAMP
ALTER_TABLE              CREATE_TABLE              FUNCTIONS         TRUNCATE 
ALTER_TYPE               CREATE_TRIGGER            GRANT             TYPES    
ALTER_USER               CREATE_TYPE               INSERT            UPDATE   
APPLY                    CREATE_USER               INSERT_JSON       USE      
ASCII                    DATE                      INT               UUID     
BATCH                    DELETE                    JSON            
BEGIN                    DROP_AGGREGATE            KEYWORDS        
BLOB                     DROP_COLUMNFAMILY         LIST_PERMISSIONS
BOOLEAN                  DROP_FUNCTION             LIST_ROLES      
COUNTER                  DROP_INDEX                LIST_USERS      
CREATE_AGGREGATE         DROP_KEYSPACE             PERMISSIONS     
CREATE_COLUMNFAMILY      DROP_MATERIALIZED_VIEW    REVOKE          
CREATE_FUNCTION          DROP_ROLE                 SELECT          
CREATE_INDEX             DROP_TABLE                SELECT_JSON

连续两个Tab键

cqlsh> 
?            BEGIN        CLEAR        CONSISTENCY  CREATE       DELETE       DESCRIBE     EXPAND       HELP         LIST         PAGING       SELECT       SHOW         TRACING      UPDATE       exit         
ALTER        CAPTURE      CLS          COPY         DEBUG        DESC         DROP         GRANT        INSERT       LOGIN        REVOKE       SERIAL       SOURCE       TRUNCATE     USE          quit

查询有哪些keyspace

cqlsh> DESC KEYSPACES 
system_traces  system_schema  system_auth  system  system_distributed

选择keyspace

cqlsh> use system_schema ;
cqlsh:system_schema> 

查看tables

cqlsh:system_schema> desc tables;
tables     triggers    views    keyspaces  dropped_columns
functions  aggregates  indexes  types      columns        
cqlsh:system_schema> 

查询数据

cqlsh:system_schema> select * from keyspaces;

 keyspace_name      | durable_writes | replication
--------------------+----------------+-------------------------------------------------------------------------------------
        system_auth |           True | {'class': 'org.apache.cassandra.locator.SimpleStrategy', 'replication_factor': '1'}
      system_schema |           True |                             {'class': 'org.apache.cassandra.locator.LocalStrategy'}
 system_distributed |           True | {'class': 'org.apache.cassandra.locator.SimpleStrategy', 'replication_factor': '3'}
             system |           True |                             {'class': 'org.apache.cassandra.locator.LocalStrategy'}
      system_traces |           True | {'class': 'org.apache.cassandra.locator.SimpleStrategy', 'replication_factor': '2'}

(5 rows)
cqlsh:system_schema> select * from keyspaces where keyspace_name='system_auth';//注意不能用双引号，不然语法错误

 keyspace_name | durable_writes | replication
---------------+----------------+-------------------------------------------------------------------------------------
   system_auth |           True | {'class': 'org.apache.cassandra.locator.SimpleStrategy', 'replication_factor': '1'}

(1 rows)

增删改查和mysql的语句差不多