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Accumulo provides a mechanism to export and import tables.  This README shows
how to use this feature.

The shell session below shows creating a table, inserting data, and exporting
the table.  A table must be offline to export it, and it should remain offline
for the duration of the distcp.  An easy way to take a table offline without
interuppting access to it is to clone it and take the clone offline.

  root@test15> createtable table1
  root@test15 table1> insert a cf1 cq1 v1
  root@test15 table1> insert h cf1 cq1 v2
  root@test15 table1> insert z cf1 cq1 v3
  root@test15 table1> insert z cf1 cq2 v4
  root@test15 table1> addsplits -t table1 b r
  root@test15 table1> scan
  a cf1:cq1 []    v1
  h cf1:cq1 []    v2
  z cf1:cq1 []    v3
  z cf1:cq2 []    v4
  root@test15> config -t table1 -s table.split.threshold=100M
  root@test15 table1> clonetable table1 table1_exp
  root@test15 table1> offline table1_exp
  root@test15 table1> exporttable -t table1_exp /tmp/table1_export
  root@test15 table1> quit

After executing the export command, a few files are created in the hdfs dir.
One of the files is a list of files to distcp as shown below.

  $ hadoop fs -ls /tmp/table1_export
  Found 2 items
  -rw-r--r--   3 user supergroup        162 2012-07-25 09:56 /tmp/table1_export/distcp.txt
  -rw-r--r--   3 user supergroup        821 2012-07-25 09:56 /tmp/table1_export/exportMetadata.zip
  $ hadoop fs -cat /tmp/table1_export/distcp.txt
  hdfs://n1.example.com:6093/accumulo/tables/3/default_tablet/F0000000.rf
  hdfs://n1.example.com:6093/tmp/table1_export/exportMetadata.zip

Before the table can be imported, it must be copied using distcp.  After the
discp completed, the cloned table may be deleted.

  $ hadoop distcp -f /tmp/table1_export/distcp.txt /tmp/table1_export_dest

The Accumulo shell session below shows importing the table and inspecting it.
The data, splits, config, and logical time information for the table were
preserved.

  root@test15> importtable table1_copy /tmp/table1_export_dest
  root@test15> table table1_copy
  root@test15 table1_copy> scan
  a cf1:cq1 []    v1
  h cf1:cq1 []    v2
  z cf1:cq1 []    v3
  z cf1:cq2 []    v4
  root@test15 table1_copy> getsplits -t table1_copy
  b
  r
  root@test15> config -t table1_copy -f split
  ---------+--------------------------+-------------------------------------------
  SCOPE    | NAME                     | VALUE
  ---------+--------------------------+-------------------------------------------
  default  | table.split.threshold .. | 1G
  table    |    @override ........... | 100M
  ---------+--------------------------+-------------------------------------------
  root@test15> tables -l
  !METADATA       =>         !0
  trace           =>          1
  table1_copy     =>          5
  root@test15 table1_copy> scan -t !METADATA -b 5 -c srv:time
  5;b srv:time []    M1343224500467
  5;r srv:time []    M1343224500467
  5< srv:time []    M1343224500467