查詢資料
get 'bjcjtest1_hdrive_2000'
,"\x00\x80\x03\x8d\x96\xa9\xdco\xb6"
scan 'tts_201905'
,
get多版本get 't1'
,'rowkey1'
,
字首過濾掃瞄scan 'station429_hdrive_40000'
,
通過hbase shell命令觸發compactionmajor_compact
檢視meta表scan 'hbase:meta'
檢視表資料,scan過濾器scan 'station428_hdrive_40000'
,scan 'users'
,scan 'users'
,scan 'users'
,scan 'users'
,scan 'users'
,scan 'users',/
/指定多個列字首。
scan 'users',/
/從列a開始,到c之前的
scan 'tts_201905'
,scan 'users'
,scan 'testbycrq'
,filter=>"rowfilter(=,'substring:111')"
scan 'testbycrq'
,filter=>"rowfilter(=,'binary:0111486816556')"
scan 'testbycrq'
,filter=>"rowfilter(<=,'binary:0111486816556')"
scan 'table'
,filter=>"rowfilter(=,'regexstring:.2')"
scan 'table'
,filter=>"rowfilter(=,'regexstring:row2.')"
scan 'test1'
,scan 'test1'
,scan 'test1'
,filter=>"columnprefixfilter('s') and ( valuefilter(=,'substring:123') or valuefilter(=,'substring:222') )"
scan 『tweet0』,
scan 『tweet0』,
scan 『tweet0』,
scanner規範:
timerange,
filter,
limit,
startrow(start row),
stoprow(stop row),
rowprefixfilter(row prefix filter,行字首)
timestamp,
maxlength,
or columns,
cache,
or raw,
versions
snapshot
snapshot 'mytable'
,'mytablesnapshot-122112'
listing snapshotslist_snapshots
deleting snapshotsdelete_snapshot 'mytablesnapshot-122112'
restore a snapshotdisable 'mytable'
restore_snapshot 'mytablesnapshot-122112'
起始查詢,返回結果不包括結束值scan 'testtable'
,
建立預分割槽表create 'testsplit444'
,'f'
, splits => [
'999trnv986rtpivo'
,'h88jfuxlij5l5t5k'
,'po4fdzxo4ifld24z'
]create 'split_table_test'
,'cf'
,create 't3'
,'f1'
,
檢視region資訊status '******'
檢測normalizer狀態和enable/disable normalizernormalizer_enabled
normalizer_switch false
建表以後改壓縮格式及**政策alter 'ts001_201905'
, name => 'f'
, compression => 'gz'
alter 'tablename',}
create 'test2'
,'cf2',}
create 'test',}
,alter 'tts_201905',}
,
pytorch 多GPU訓練(單機多卡 多機多卡)
首先是資料集的分布處理 需要用到的包 torch.utils.data.distributed.distributedsampler torch.utils.data.dataloader torch.utils.data.dataset distributedsampler這個包我們用來確保dat...
雙向多對多
雙向多對多會通過乙個中間表來維持關聯關係 雙向多對多關係中必須指定乙個關係維護端 否則中間表裡會出現主鍵重複的問題 例如 標籤類tags和商品類goods 乙個標籤可對應多種商品 乙個商品也能有多個標籤 首先在兩個類中各建乙個對方型別的set作屬性 用到的註解解釋 商品類goods 需要用 join...
怎樣理解多對多
a表,a id,a name,a tel三個字段。b表,b id,b address,b sol三個字段。關聯表,ref id,a id,b id,儲存著ab兩表的id,比如 a有 a0001,zhang3,139555533 a0002,li4,1397788888 a0003,wang5,136...