Hypertable工具之ht_rsclient

刺骨的言语ヽ痛彻心扉 2022-08-27 07:59 81阅读 0赞

命令：ht\_rsclient  \[rangeserver\_ip:port\]。  
Ht\_rsclient命令可连接至任意一台RangeServer，并在该台RangeServer上执行下列命令：  
COMPACT ............... Schedules range compactions  
CREATE SCANNER ........ Creates a scanner and displays first block of results  
DESTROY SCANNER ....... Destroys a scanner  
DROP RANGE ............ Drop a range  
FETCH SCANBLOCK ....... Fetch the next block results of a scan  
LOAD RANGE ............ Load a range  
METADATA SYNC ......... Sync METADATA table with RSML data  
REPLAY START .......... Start replay  
REPLAY LOG ............ Replay a commit log  
REPLAY COMMIT ......... Commit replay  
SHUTDOWN   ............ Shutdown the RangeServer  
UPDATE ................ Selects (and display) cells from a table  
WAIT FOR MAINTENANCE .. Blocks until maintenance queue is empty  
**1.COMPACT **  
COMPACT TABLE table\_name  
COMPACT RANGES range\_type \['|' range\_type ...\]  
  
  
range\_type:  
    ALL  
    | ROOT  
    | METADATA  
    | SYSTEM  
    | USER  
  
  
本命令将对指定的每个Range调度执行major compaction操作。Table版本将对给定表的每个Range执行compaction，Ranges版本将对指定类型的所有Range执行compaction，不管这些Range属于哪些表。  
NOTE:  Compactions scheduled by this command are spread out over time.  
During each maintenance interval, which by default happens once every  
60 seconds, a limited number of these compactions will get scheduled  
as controlled by the following property:  
  
  
  Hypertable.RangeServer.Maintenance.MoveCompactionsPerInterval  
  
  
The default value for this property is 2.  
**1.1.COMPACT TABLE**  
Compact table “hyt/foo”; 执行foo表在该台RangeSever上的所有Range的compaction操作。  
**1.2.COMPACT RANGES**  
COMPACT RANGES all; //执行该台RangeServer上所有Range的compaction操作  
COMPACT RANGES user //执行该台RangeServer上所有USER类型的Range的compaction操作。  
**2.CREATE SCANNER**  
CREATE SCANNER ON range\_spec  
    \[where\_clause\]  
    \[options\_spec\]  
  
  
range\_spec:  
    table\_name '\[' \[start\_row\] ".." (end\_row | ?? ) '\]'  
  
  
where\_clause:  
    WHERE where\_predicate \[AND where\_predicate ...\]   
  
  
where\_predicate:   
    cell\_predicate  
    | row\_predicate  
    | timestamp\_predicate  
  
  
relop: '=' | '<' | '<=' | '>' | '>=' | '=^'  
  
  
cell\_spec: row\_key ',' qualified\_column  
  
  
cell\_predicate:   
    \[cell\_spec relop\] CELL relop cell\_spec  
    | '(' \[cell\_spec relop\] CELL relop cell\_spec  
          (OR \[cell\_spec relop\] CELL relop cell\_spec)\* ')'  
  
  
row\_predicate:   
    \[row\_key relop\] ROW relop row\_key  
    | '(' \[row\_key relop\] ROW relop row\_key  
          (OR \[row\_key relop\] ROW relop row\_key)\* ')'  
  
  
timestamp\_predicate:   
    \[timestamp relop\] TIMESTAMP relop timestamp  
  
  
options\_spec:  
    (MAX\_VERSIONS revision\_count  
    | LIMIT row\_count  
    | INTO FILE 'file\_name'  
    | DISPLAY\_TIMESTAMPS  
    | RETURN\_DELETES  
    | KEYS\_ONLY  
    | SCAN\_AND\_FILTER\_ROWS)\*  
  
  
timestamp:  
    'YYYY-MM-DD HH:MM:SS\[.ss|:nanoseconds\]'  
  
  
本命令将创建基于一个Range的scanner。如果range\_spec中缺少start\_row，则意味着NULL或者改Range的开始。如果end\_row指定为”??”，它将自动转换为OXff，这意味着Range的结尾。  
示例： CREATE SCANNER ON “dinglicom/Test”\[..??\]  
  
  
实验表明：  
1.，语法如：ht\_rsclient 172.16.23.164:38060  
2.只能连接到一个Range所在的RangeServer，才能查看该Range的数据。可查询MEATDATA表获取Range的当前位置。查询MEATDATA表时，可能会看到一个Range具有多个Location，这可能是由于Range的迁移造成的，其中时间戳最新的一个即为当前Location。  
3.查询Range时，需指定StartRow和EndRow。假设当METADATA结果如下时：  
2013-04-15 04:57:20.861318001   2/15:key1259    StartRow  
2013-04-15 04:57:20.861318004   2/15:key1259    Location        rs5  
2013-04-15 04:57:20.861318005   2/15:key1541    StartRow        key1259  
2013-04-15 04:04:00.309111001   2/15:key1541    StartRow  
2013-04-15 04:57:21.096424001   2/15:key1541    Location        rs6  
2013-04-15 04:04:00.309111004   2/15:key1541    Location        rs5  
2013-04-15 04:04:00.309111005   2/15:key29      StartRow        key1541  
2013-04-15 03:26:57.856186001   2/15:key29      StartRow  
2013-04-15 04:04:00.415763001   2/15:key29      Location        rs7  
2013-04-15 03:26:57.856186004   2/15:key29      Location        rs5  
2013-04-15 04:45:45.428110001   2/15:key549     StartRow        key29  
2013-04-15 04:45:45.428110004   2/15:key549     Location        rs3  
2013-04-15 04:45:45.428110005   2/15:tartRow    key549  
2013-04-15 03:26:57.856186005   2/15:tartRow    key29  
2013-04-15 03:10:05.131263001   2/15:tartRow  
2013-04-15 04:45:45.600951001   2/15:ocation    rs1  
2013-04-15 03:26:58.031994001   2/15:ocation    rs3  
2013-04-15 03:10:05.465607001   2/15:ocation    rs5  
则在rs5上执行“create scanner on "dingli/foo" \[.."key1259"\];”成功；在rs1上执行“create scanner on "dingli/foo" \["key549"..??\];”成功；在rs6上执行“create scanner on "dingli/foo" \["key1259"..” key1541”\];”成功。  
在METADATA结果如下时：  
2013-04-11 03:04:43.258011001   0/1:tartRow  
2013-04-11 07:40:16.784530001   0/1:ocation     rs1  
2013-04-11 03:04:43.533125001   0/1:ocation     rs2  
在rs1上执行CREATE SCANNER ON TableName\[..??\]成功。  
目前除这四种查询范围外，其余皆提示失败信息“RANGE SERVER range not found”。  
4.Where子句后的cell\_predicate和row\_predicate测试通过，其查询该Range中符合指定条件的CELL。  
5. options\_spec中的INTO FILE测试不成功，命令虽然执行成功，但在本地或者DFS上都不能找到导出的文件。  
**3.DESTROY SCANNER**  
DESTROY SCANNER \[scanner\_id\]  
  
  
This command will destroy a scanner previously created with  
a CREATE SCANNER command.  If a scanner\_id is supplied, then  
the scanner corresponding to that ID will be destroyed, otherwise  
the "current" or most recently created scanner will get destroyed.  
**4.LOAD RANGE**  
LOAD RANGE range\_spec  
  
  
range\_spec:  
    table\_name '\[' \[start\_row\] ".." (end\_row | ?? ) '\]'  
  
  
This command will issue a 'load range' command to the RangeServer  
for the range specified with range\_spec.  
**5.DROP RANGE**  
DROP RANGE range\_spec  
  
  
range\_spec:  
    table\_name '\[' \[start\_row\] ".." (end\_row | ?? ) '\]'  
  
  
该命令将发送一条删除指定Range的命令到RangeServer，即该命令虽然最终会导致一个Range的删除，但是可能会有延迟，因为删除并不是由该命令直接完成。  
  
  
实验表明：  
例如：当查询METADATA时，结果中出现：  
2013-04-15 04:57:20.861318005   2/15:key1541    StartRow        key1259  
2013-04-15 04:04:00.309111001   2/15:key1541    StartRow  
2013-04-15 04:57:21.096424001   2/15:key1541    Location        rs6  
2013-04-15 04:04:00.309111004   2/15:key1541    Location        rs5  
则执行“drop RANGE on "dingli/foo" \["key1541".."key2166"\];”，该Range将被删除。观察监控界面该表的Range Count数量将减1，并且查询该Range中的rowkey时，将在RangeServer的log中提示“Range not found”。  
**6.METADATA SYNC**   
METADATA SYNC TABLE table\_name \[options\_spec\]  
METADATA SYNC RANGES range\_type \['|' range\_type ...\] \[options\_spec\]  
  
  
range\_type:  
    ALL  
    | ROOT  
    | METADATA  
    | SYSTEM  
    | USER  
  
  
options\_spec:  
    COLUMNS=<columns>  
  
  
This command re-writes columns of the METADATA table, for a set of  
ranges, using data from the RSML.  The TABLE version of the command  
re-writes METADATA for the ranges in the given table.  The RANGES  
version of the command re-writes METADATA for all ranges of the  
given type(s), regardless of what table they belong to.  
**6.1.METADATA SYNC TABLE  
6.2.METADATA SYNC RANGES  
7.SHUTDOWN**  
This command causes the RangeServer to shutdown.  It will  
return immediately, but the RangeServer will wait for all  
running requests to complete before shutting down.  
**8.UPDATE **  
UPDATE table\_name input\_file  
  
  
This command will read blocks of key/value pairs from input\_file  
and send them to the range server.  Here are some example input file  
lines that illustrate the format of this file:  
  
  
1189631331826108        acaleph DELETE  
1189631331826202        acrostolion     apple:http://www.baseball.com/       Vilia miretur vulgus  
1189631331826211        acerin  banana:http://sports.espn.go.com/       DELETE  
  
  
The fields are separated by the tab character, with the following format:  
<timestamp> '\\t' <row-key> '\\t' <column-family>\[:<column-qualfier>\] '\\t' <value>  
  
  
The string "DELETE" has special meaning.  In the first example line  
above, it generates a 'delete row' for the row key 'acaleph'.  In the  
third example line above, it generates a 'delete cell' for the column  
'banana:http://sports.espn.go.com/' of row 'acerin'.