Question

我一直在使用Cassandra的2.1.4版Python驱动程序来检索一些数据。我运行了下面列出的一些简单的SELECT * from table语句：

import cassandra.cluster as cc

# connecting to localhost
db = cc.Cluster(); 
session = db.connect(keyspace)

# statment is a simple select
session.execute(boundStmt)

我可以成功地取回我的结果，但是，在结果返回之前我看到了一堆警告，如下所示。

不知道它们是什么，有没有办法解决这个问题？我的Cassandra版本是2.1.2。

WARNING:cassandra.metadata:Building table metadata with no column meta for system.IndexInfo
WARNING:cassandra.metadata:Building table metadata with no column meta for system.batchlog
WARNING:cassandra.metadata:Building table metadata with no column meta for system.compaction_history
WARNING:cassandra.metadata:Building table metadata with no column meta for system.compactions_in_progress
WARNING:cassandra.metadata:Building table metadata with no column meta for system.hints
WARNING:cassandra.metadata:Building table metadata with no column meta for system.local
WARNING:cassandra.metadata:Building table metadata with no column meta for system.paxos
WARNING:cassandra.metadata:Building table metadata with no column meta for system.peer_events
WARNING:cassandra.metadata:Building table metadata with no column meta for system.peers
WARNING:cassandra.metadata:Building table metadata with no column meta for system.range_xfers
WARNING:cassandra.metadata:Building table metadata with no column meta for system.schema_columnfamilies
WARNING:cassandra.metadata:Building table metadata with no column meta for system.schema_columns
WARNING:cassandra.metadata:Building table metadata with no column meta for system.schema_keyspaces
WARNING:cassandra.metadata:Building table metadata with no column meta for system.schema_triggers
WARNING:cassandra.metadata:Building table metadata with no column meta for system.schema_usertypes
WARNING:cassandra.metadata:Building table metadata with no column meta for system.sstable_activity

Answer 1

当你查看来源时，他们会链接到这里的票证(CASSANDRA-8487)：

def _build_table_metadata(self, keyspace_metadata, row, col_rows, trigger_rows):
    cfname = row["columnfamily_name"]
    cf_col_rows = col_rows.get(cfname, [])

    if not cf_col_rows:  # CASSANDRA-8487
        log.warning("Building table metadata with no column meta for %s.%s",
                    keyspace_metadata.name, cfname)

您所遇到的问题似乎是（间歇性）错误（某些节点在某些情况下对所有列都有一致的元数据），这些错误在2.1.3中被关闭为“不可重复”。

也许您可以尝试更新以查看问题是否仍然存在。

表元数据上的Cassandra Python驱动程序警告

1 个答案: