当我使用cql与cli进行比较时，我看到在我的列族中创建了额外的列。
使用cql创建表并插入行：

cqlsh:cassandraSample> CREATE TABLE bedbugs(
               ...     id varchar,
               ...     name varchar,
               ...     description varchar,
               ...     primary key(id, name)
               ... )  ;

cqlsh:cassandraSample> insert into bedbugs (id, name, description) 
values ('Cimex','Cimex lectularius','http://en.wikipedia.org/wiki/Bed_bug');

现在使用cli插入列：

[default@cassandraSample] set bedbugs['BatBedBug']['C. pipistrelli:description']='google.com';
Value inserted.
Elapsed time: 1.82 msec(s).
[default@cassandraSample] list bedbugs
...     ;
Using default limit of 100
Using default column limit of 100
-------------------
RowKey: Cimex
=> (column=Cimex lectularius:, value=, timestamp=1369682957658000)
=> (column=Cimex lectularius:description, value=http://en.wikipedia.org/wiki/Bed_bug, timestamp=1369682957658000)
-------------------
RowKey: BatBedBug
=> (column=C. pipistrelli:description, value=google.com, timestamp=1369688651442000)

2 Rows Returned.

cqlsh:cassandraSample> select * from bedbugs;

 id        | name              | description
-----------+-------------------+--------------------------------------
     Cimex | Cimex lectularius | http://en.wikipedia.org/wiki/Bed_bug
 BatBedBug |    C. pipistrelli |                           google.com

因此，cql为每一行创建一个额外的列，其中包含空的非主键列。这不是浪费空间吗？