Create Columnfamily problem with Cassandra from CLI

Question

I'm a beginner in Cassandra and noSQL data base. For my exam i have to correct some instruction that the professor gave me. I have corrected some of these, but now i'm not able to fix this:

cqlsh> create COLUMNFAMILY post
   ... with comparator = UTF8Type
   ... and read_repair_chance = 0.1
   ... and keys_cached = 100
   ... and gc_grace = 0
   ... and min_compaction_threshold = 5
   ... and max_compaction_threshold = 31

I receive this error from CLI:

SyntaxException: line 2:0 mismatched input 'with' expecting '(' (create COLUMNFAMILY post[with] comparator...)

I would be really grateful if somebody can help me.

I hope it is understandable because my English isn't very good

Answer 1

Your columnfamily definition, or table definition (which is the more recent term for Cassandra tables) is missing the actual columns and a primary key, and it seems you have mixed your column definition (comparator = UTF8Type) with your table options, such as read_repair_chance and gc_grace_period.

All Cassandra tables must have at least one primary key column.

To create a minimal table post in the keyspace ks with default table options, you can do this:

CREATE TABLE ks.post (comparator text PRIMARY KEY);

To inspect the table definition and the full syntax for setting the table options:

describe table ks.post;

CREATE TABLE ks.post (
    comparator text PRIMARY KEY
) WITH 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 crc_check_chance = 1.0
    AND default_time_to_live = 0
    AND gc_grace_seconds = 864000
    AND max_index_interval = 2048
    AND memtable_flush_period_in_ms = 0
    AND min_index_interval = 128
    AND speculative_retry = '99PERCENTILE';

Note: if you are using default table options, you do not have to specify them in your table creation command.

For documentation about table creation, check here for example: https://docs.datastax.com/en/dse/5.1/cql/cql/cql_reference/cql_commands/cqlCreateTable.html

or here: http://cassandra.apache.org/doc/latest/cql/ddl.html#create-table