TTL(Time To Live)生存期
hbase表默认保存一个版本的数据
hbase(main):123:0> create \'t_name\',\'st1\'
Created table t_name
Took 1.3807 seconds
=> Hbase::Table - t_name
hbase(main):124:0> desc \'t_name\'
Table t_name is ENABLED
t_name
COLUMN FAMILIES DESCRIPTION
{NAME => \'st1\', VERSIONS => \'1\', EVICT_BLOCKS_ON_CLOSE => \'false\', NEW_VERSION_BEHAVIOR => \'false\', KEEP_DELETED_CELLS => \'FALSE\', CACHE_DATA_ON_WRITE => \'false\', DATA_BLOCK_ENC
ODING => \'NONE\', TTL => \'FOREVER\', MIN_VERSIONS => \'0\', REPLICATION_SCOPE => \'0\', BLOOMFILTER => \'ROW\', CACHE_INDEX_ON_WRITE => \'false\', IN_MEMORY => \'false\', CACHE_BLOOMS_ON_WR
ITE => \'false\', PREFETCH_BLOCKS_ON_OPEN => \'false\', COMPRESSION => \'NONE\', BLOCKCACHE => \'true\', BLOCKSIZE => \'65536\'}
1 row(s)
Took 0.0310 seconds
添加一个列族
hbase(main):126:0> alter \'t_name\',{NAME=>\'st2\'}
Updating all regions with the new schema...
All regions updated.
Done.
Took 1.5367 seconds
hbase(main):127:0> desc \'t_name\'
Table t_name is DISABLED
t_name
COLUMN FAMILIES DESCRIPTION
{NAME => \'st1\', VERSIONS => \'1\', EVICT_BLOCKS_ON_CLOSE => \'false\', NEW_VERSION_BEHAVIOR => \'false\', KEEP_DELETED_CELLS => \'FALSE\', CACHE_DATA_ON_WRITE => \'false\', DATA_BLOCK_ENC
ODING => \'NONE\', TTL => \'FOREVER\', MIN_VERSIONS => \'0\', REPLICATION_SCOPE => \'0\', BLOOMFILTER => \'ROW\', CACHE_INDEX_ON_WRITE => \'false\', IN_MEMORY => \'false\', CACHE_BLOOMS_ON_WR
ITE => \'false\', PREFETCH_BLOCKS_ON_OPEN => \'false\', COMPRESSION => \'NONE\', BLOCKCACHE => \'true\', BLOCKSIZE => \'65536\'}
{NAME => \'st2\', VERSIONS => \'1\', EVICT_BLOCKS_ON_CLOSE => \'false\', NEW_VERSION_BEHAVIOR => \'false\', KEEP_DELETED_CELLS => \'FALSE\', CACHE_DATA_ON_WRITE => \'false\', DATA_BLOCK_ENC
ODING => \'NONE\', TTL => \'FOREVER\', MIN_VERSIONS => \'0\', REPLICATION_SCOPE => \'0\', BLOOMFILTER => \'ROW\', CACHE_INDEX_ON_WRITE => \'false\', IN_MEMORY => \'false\', CACHE_BLOOMS_ON_WR
ITE => \'false\', PREFETCH_BLOCKS_ON_OPEN => \'false\', COMPRESSION => \'NONE\', BLOCKCACHE => \'true\', BLOCKSIZE => \'65536\'}
2 row(s)
Took 0.0147 seconds
修改版本数：
hbase(main):151:0> alter \'t_name\',{NAME=>\'st1\'},{NAME=>\'st1\',VERSIONS=>5}
Updating all regions with the new schema...
1/1 regions updated.
Done.
Took 3.6029 seconds
插入数据：
hbase(main):128:0> enable \'t_name\'
Took 1.2686 seconds
hbase(main):129:0> put \'t_name\',\'1\',\'st1:name\',\'xiaoma\'
Took 0.0060 seconds
hbase(main):146:0> put \'t_name\',\'1\',\'st1:age\',\'30\'
Took 0.0024 seconds
hbase(main):155:0> put \'t_name\',\'1\',\'st1:age\',100
Took 0.0028 seconds
hbase(main):157:0> put \'t_name\',\'1\',\'st1:age\',88
Took 0.0022 seconds
同一单元写入3次，查询：
hbase(main):158:0> scan \'t_name\'
ROW COLUMN+CELL
1 column=st1:age, timestamp=1526971520170, value=88
1 column=st1:name, timestamp=1526971227081, value=xiaoma
1 column=st2:level, timestamp=1526971286607, value=50
1 row(s)
Took 0.0042 seconds
hbase(main):173:0> get \'t_name\',\'1\'
COLUMN CELL
st1:age timestamp=1526971520170, value=88
st1:name timestamp=1526971227081, value=xiaoma
st2:level timestamp=1526971286607, value=50
1 row(s)
Took 0.0037 seconds
发现查询结果为最后一次写入的值
查看历史版本：
hbase(main):174:0> get \'t_name\',1,{COLUMN=>\'st1:age\',VERSIONS=>1}
COLUMN CELL
st1:age timestamp=1526971520170, value=88
1 row(s)
Took 0.0055 seconds
hbase(main):175:0> get \'t_name\',1,{COLUMN=>\'st1:age\',VERSIONS=>2}
COLUMN CELL
st1:age timestamp=1526971520170, value=88
st1:age timestamp=1526971419514, value=100
1 row(s)
Took 0.0032 seconds
hbase(main):176:0> get \'t_name\',1,{COLUMN=>\'st1:age\',VERSIONS=>3}
COLUMN CELL
st1:age timestamp=1526971520170, value=88
st1:age timestamp=1526971419514, value=100
st1:age timestamp=1526971266685, value=30
1 row(s)
Took 0.0044 seconds
hbase(main):193:0> get \'t_name\',\'1\',{COLUMN=> \'st1:age\',TIMERANGE => [1526971266685,1526971520170] ,VERSIONS => 4}
COLUMN CELL
st1:age timestamp=1526971419514, value=100
st1:age timestamp=1526971266685, value=30
1 row(s)
Took 0.0039 seconds
hbase(main):194:0> get \'t_name\',\'1\',{COLUMN=>\'st1:age\',TIMESTAMP=>1526971419514,VERSIONS=>4}
COLUMN CELL
st1:age timestamp=1526971419514, value=100
1 row(s)
Took 0.0028 seconds