阅读Cassandra 1.2表与pycassa [英] Reading Cassandra 1.2 table with pycassa

问题描述

使用Cassandra 1.2。我使用CQL 3创建了一个表格，如下：

  CREATE TABLE foo（
 user text PRIMARY KEY，
电子邮件集< text> 
）; 
  

现在我想通过pycassa查询数据：

  import pycassa 
 from pycassa.pool import ConnectionPool 
 pool = ConnectionPool（'ks1'，['localhost：9160']）
 foo = pycassa.ColumnFamily（pool，'foo'）
  

这给我

 跟踪（最近一次调用）：
文件test.py，第5行，在< module> 
 foo = pycassa.ColumnFamily（pool，'foo'）
文件/home/john/src/pycassa/lib/python2.7/site-packages/pycassa/columnfamily.py，第284行，in __init__ 
 self.load_schema（）
文件/home/john/src/pycassa/lib/python2.7/site-packages/pycassa/columnfamily.py，第312行，在load_schema 
 raise nfe 
 pycassa.cassandra.ttypes.NotFoundException：NotFoundException（_message = None，why ='Column family foo not found。）
  
解决方案
如果您已经创建了表使用CQL3，你想通过基于thrift的客户端访问它们;您将必须指定紧凑存储属性。例如：
  CREATE TABLE dummy_file_test 
（
 dtPtn INT，
 pxID INT，
 startTm INT，
 endTm INT，
 patID BIGINT，
 efile BLOB，
 PRIMARY KEY（（dtPtn，pxID，startTm））
） 
 
这是我在访问基于CQL3的列使用Pycassa时所必须做的
 
Using Cassandra 1.2. I created a table using CQL 3 the following way:
CREATE TABLE foo (
    user text PRIMARY KEY,
    emails set<text>
);
Now I am trying to query the data through pycassa:
import pycassa
from pycassa.pool import ConnectionPool
pool = ConnectionPool('ks1', ['localhost:9160'])
foo = pycassa.ColumnFamily(pool, 'foo')
This gives me
Traceback (most recent call last):
  File "test.py", line 5, in <module>
    foo = pycassa.ColumnFamily(pool, 'foo')
  File "/home/john/src/pycassa/lib/python2.7/site-packages/pycassa/columnfamily.py", line 284, in __init__
    self.load_schema()
  File "/home/john/src/pycassa/lib/python2.7/site-packages/pycassa/columnfamily.py", line 312, in load_schema
    raise nfe
pycassa.cassandra.ttypes.NotFoundException: NotFoundException(_message=None, why='Column family foo not found.')
How can this be accomplished?
解决方案
If you have created your tables using CQL3 and you want to access them through a thrift based client; you will have to specify the Compact Storage property. e.g :
CREATE TABLE dummy_file_test
(
 dtPtn          INT,
 pxID           INT,
 startTm        INT,
 endTm          INT,
 patID          BIGINT,
 efile          BLOB,
 PRIMARY KEY((dtPtn, pxID, startTm))
)with compact storage;  
This is what i had to do while accessing CQL3 based column Families with Pycassa

                        
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