=====Database Operations=====
For a NoSQL, Cassandra seems more as SQL Database (Oracle, DB2, etc) than NoSQL databases (Mongo for example)
A lot of the commands are the same as SQL datatabase, as you will see below:

====Connection====
First and foremost, we have to connect to our cassandra :) Cassandra uses a lot of ports and knowing which ports to use is essential:


Cassandra
  *     7199 JMX monitoring port and in earlier Cassandra (0.8) version it was 8080
  *     9042 CQL Native Transport Port
  *     9160 Thrift client API
  *     7000 Inter-node cluster
  *     7001 TLS Internode communication (used if TLS enabled)

DataStax OpsCenter
  *     61620 opscenterd daemon
  *     61621 Agent
  *     8888 Website

So for our connection we will use port: 9042, which is the native CQL client port, as follows:


<sxh bash>
$ cqlsh 172.27.1.246 9042  -u jandonov -p XXXXXXXXXXXXXXXXXXXXX
    ^         ^        ^         ^               ^
    |         |        |         |               |
  Client IP Address  Port     Username        Password
  
[cqlsh 5.0.1 | Cassandra 3.10 | CQL spec 3.4.4 | Native protocol v4]
Use HELP for help.
jandonov@cqlsh> SELECT * FROM system_schema.keyspaces;

 keyspace_name      | durable_writes | replication
</sxh>

====Schemas/Databases====
Schemas/Databases, also known as keyspaces, are created as follows:

<sxh bash>
cqlsh> CREATE KEYSPACE testkeyspace WITH replication = {'class':'SimpleStrategy', 'replication_factor': '3'} AND durable_writes = true;
cqlsh>  DESCRIBE testkeyspace;

CREATE KEYSPACE testkeyspace WITH replication = {'class': 'SimpleStrategy', 'replication_factor': '3'}  AND durable_writes = true;

cqlsh>

cqlsh> SELECT * FROM system_schema.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'}
       testkeyspace |           True | {'class': 'org.apache.cassandra.locator.SimpleStrategy', 'replication_factor': '3'}
      system_traces |           True | {'class': 'org.apache.cassandra.locator.SimpleStrategy', 'replication_factor': '2'}

(6 rows)
cqlsh>
</sxh>


====Table====
Tables, also known as column families, are created within a schema/database as follows:


<sxh bash>
cqlsh> use testkeyspace;
cqlsh:testkeyspace>
cqlsh:testkeyspace> CREATE TABLE testTable (
                ...     id int,
                ... name text,
                ... primary key(id)
                ... ) WITH read_repair_chance = 0.0
                ...    AND dclocal_read_repair_chance = 0.1
                ...    AND gc_grace_seconds = 864000
                ...    AND bloom_filter_fp_chance = 0.01
                ...    AND caching = { 'keys' : 'ALL', 'rows_per_partition' : 'NONE' }
                ...    AND comment = ''
                ...    AND compaction = { 'class' : 'org.apache.cassandra.db.compaction.SizeTieredCompactionStrategy', 'max_threshold' : 32, 'min_threshold' : 4 }
                ...    AND compression = { 'chunk_length_in_kb' : 64, 'class' : 'org.apache.cassandra.io.compress.LZ4Compressor' }
                ...    AND default_time_to_live = 0
                ...    AND speculative_retry = '99PERCENTILE'
                ...    AND min_index_interval = 128
                ...    AND max_index_interval = 2048
                ...    AND crc_check_chance = 1.0;
cqlsh:testkeyspace>
cqlsh:testkeyspace>
</sxh>


====Insert====
Inserts are also done pretty easily:

<sxh bash>
cqlsh:testkeyspace> select * from testTable;

 id | name
----+------

(0 rows)
cqlsh:testkeyspace> insert into testTable values(1,'Julien');
SyntaxException: line 1:22 no viable alternative at input 'values' (insert into [testTable] values...)
cqlsh:testkeyspace> insert into testTable(id,name) values(1,'Julien');
cqlsh:testkeyspace> select * from testTable;

 id | name
----+--------
  1 | Julien

(1 rows)
cqlsh:testkeyspace>
</sxh>


====Create users====
Users in Cassandra can have either super(all privileges) role or objects privileges for objects. In order to list all the users, use the following command:


<Code: none | List Users>
 name       | super
------------+-------
     casbak | False
      games | False
  games_fun | False
 games_real | False
   jandonov |  True
    kharole | False
  millichev | False
  pdudenkov | False

</Code>

To create new user, we can do as follows:


<Code: none | Create users>
jandonov@cqlsh> create user andriin123 with password 'PASSWORD1';
jandonov@cqlsh> grant dev to adriin;
jandonov@cqlsh> list users;

 name        | super
-------------+-------
     andriin123 | False
</Code>