[HBASE-3271] Allow .META. table to be exported

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.20.6
• Fix Version/s: 0.94.2
• Component/s: util
• Hadoop Flags: Reviewed
• Release Note: mapreduce.Export is able to export .META. table
• Assignee: Liang Xie
• Reporter: Ted Yu
• Created: 23/Nov/10 21:56
• Updated: 07/Apr/13 05:08
• Resolved: 24/Aug/12 16:41

Description

I tried to export .META. table in 0.20.6 and got:

[hadoop@us01-ciqps1-name01 hbase]$ bin/hbase org.apache.hadoop.hbase.mapreduce.Export .META. h-meta 1 0 0
10/11/23 20:59:05 INFO jvm.JvmMetrics: Initializing JVM Metrics with processName=JobTracker, sessionId=
2010-11-23 20:59:05.255::INFO: Logging to STDERR via org.mortbay.log.StdErrLog
2010-11-23 20:59:05.255::INFO: verisons=1, starttime=0, endtime=9223372036854775807
10/11/23 20:59:05 INFO zookeeper.ZooKeeper: Client environment:zookeeper.version=3.2.2-888565, built on 12/08/2009 21:51 GMT
10/11/23 20:59:05 INFO zookeeper.ZooKeeper: Client environment:host.name=us01-ciqps1-name01.carrieriq.com
10/11/23 20:59:05 INFO zookeeper.ZooKeeper: Client environment:java.version=1.6.0_21
10/11/23 20:59:05 INFO zookeeper.ZooKeeper: Client environment:java.vendor=Sun Microsystems Inc.
...
10/11/23 20:59:05 INFO zookeeper.ClientCnxn: Server connection successful
10/11/23 20:59:05 DEBUG zookeeper.ZooKeeperWrapper: Read ZNode /hbase/root-region-server got 10.202.50.112:60020
10/11/23 20:59:05 DEBUG client.HConnectionManager$TableServers: Found ROOT at 10.202.50.112:60020
10/11/23 20:59:05 DEBUG client.HConnectionManager$TableServers: Cached location for .META.,,1 is us01-ciqps1-grid02.carrieriq.com:60020
Exception in thread "main" java.io.IOException: Expecting at least one region.
at org.apache.hadoop.hbase.mapreduce.TableInputFormatBase.getSplits(TableInputFormatBase.java:281)
at org.apache.hadoop.mapred.JobClient.writeNewSplits(JobClient.java:885)
at org.apache.hadoop.mapred.JobClient.submitJobInternal(JobClient.java:779)
at org.apache.hadoop.mapreduce.Job.submit(Job.java:432)
at org.apache.hadoop.mapreduce.Job.waitForCompletion(Job.java:447)
at org.apache.hadoop.hbase.mapreduce.Export.main(Export.java:146)

Related code is:
if (keys == null || keys.getFirst() == null ||
keys.getFirst().length == 0)

{ throw new IOException("Expecting at least one region."); }

My intention was to save the dangling rows in .META. (for future investigation) which prevented a table from being created.