Question

我有一个带有TEXT类型的空列的Cassandra表，它出现在DESCRIBE TABLE中但不出现在SELECT列FROM表，ALTER TABLE表DROP列或ALTER TABLE表RENAME列TO new_column中。如何在不丢失任何数据的情况下删除此列？

这是一个3节点集群。 /var/log/cassandra/system.log,cassandra.log或debug.log中没有记录错误。

nodetool upgradedesstables和nodetool repair都没有报告任何错误。每个都在集群的所有3个节点上执行。

$ cqlsh 192.168.1.1 9042
Connected to my_laptop at 192.168.1.1:9042.
[cqlsh 5.0.1 | Cassandra 3.0.9 | CQL spec 3.4.0 | Native protocol v4]


CREATE TABLE proj.stuff (
    my_id uuid PRIMARY KEY,
    her_id uuid,
    her_name text,
    my_odd_column text,
    status boolean
) WITH bloom_filter_fp_chance = 0.01
    AND caching = {'keys': 'ALL', 'rows_per_partition': 'NONE'}
    AND comment = 'Stores Initiative Entity for MyProject'
    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 dclocal_read_repair_chance = 0.1
    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 read_repair_chance = 0.0
    AND speculative_retry = '99PERCENTILE';

cqlsh:proj> ALTER TABLE stuff RENAME my_odd_column TO old_my_odd_column;
InvalidRequest: Error from server: code=2200 [Invalid query] message="Cannot     
rename unknown column my_odd_column in keyspace stuff"

注意：错误消息中的键空间名称错误，它实际上是表名

cqlsh:proj> ALTER TABLE stuff DROP my_odd_column;
InvalidRequest: Error from server: code=2200 [Invalid query] message="Column    
my_odd_column was not found in table stuff"

cqlsh:proj> SELECT my_id, my_odd_column FROM stuff;
InvalidRequest: Error from server: code=2200 [Invalid query]         
message="Undefined name my_odd_column in selection clause"

Cassandra ALTER TABLE DROP列失败，表中未找到

0 个答案: