HPE Ezmeral Data Fabric Database JSON ExportTable and ImportTable
Use these utilities together to export data from JSON tables into binary sequence
files, and then import the data from the binary sequence files into other JSON tables. You can also use the
mapr importtable
utility to import changes that are specified in sequence
files output by the mapr difftables
utility.
Required Permissions
- The
readAce
permission on the volume where the source table formapr exporttable
is located. - The
writeAce
permission on the volume in which to save the output frommapr exporttable
. - The
readAce
permission on the volume where the files output bymapr exporttable
is located. - The
writeAce
permission on the volume in which the destination table is located.
For information about how to set permissions on volumes, see Setting Whole Volume ACEs.
mapr
user is not treated as a
superuser. HPE Ezmeral Data Fabric Database does not allow the mapr
user to run these utilities unless that user is given the relevant permission or permissions
with access-control expressions.Syntax of mapr exporttable
mapr exporttable
(option)
-src Name of table
-dst Directory path
[-columns Fields to include]
[-mapreduce : <true|false>, default is true]
Parameters of mapr exporttable
Parameter | Description |
---|---|
src | The path of the JSON table to export from. |
dst | The directory within the Data Fabric file system to export the files to. |
columns | A comma-delimited list of fields to include in the exported files.
Example Do not use quotation marks and do
not include spaces after commas. |
mapreduce |
The cluster must have YARN installed and configured for this option to work. A Boolean value that specifies whether or not to
use a MapReduce program to perform the operation. The default, preferred method is
to use a MapReduce program ( When this parameter is set to |
Syntax of mapr importtable
mapr importtable
(option)
-src Input binary file or directory path
-dst Destination table
[-bulkload <true|false>, default is false ]
[-mapreduce : <true|false>, default is true]
Parameters of mapr importtable
Parameter | Description |
---|---|
src | The path of the binary file or files to import.
Examples
|
dst | The JSON table to import the data into. |
bulkload | A Boolean value that specifies whether or not
to perform a full bulk load of the table. The default is not to use bulk loading
(false ). To use bulk load, you must set the
-bulkload parameter of the table to true by
running the command maprcli table edit -path <path to table> -bulkload
true . |
mapreduce |
The cluster must have YARN installed and configured for this option to work. A Boolean value that specifies whether or not to
use a MapReduce program to perform the operation. The default, preferred method is
to use a MapReduce program ( When this parameter is set to |
Example of using mapr exporttable
and
mapr importtable
together
[user@hostname ~]$ mapr exporttable -columns contributors,creditLine -src /collection/artworks -dst /tempExport
Header: hostName: hostname, Time Zone: Pacific Standard Time, processName: null, processId: null
2015-10-01 23:02:38,044 INFO org.apache.hadoop.io.compress.zlib.ZlibFactory <clinit> pool-2-thread-1: Successfully loaded & initialized native-zlib library
2015-10-01 23:02:38,059 INFO org.apache.hadoop.io.compress.CodecPool getCompressor pool-2-thread-1: Got brand-new compressor [.deflate]
[user@hostname ~]$ hadoop mfs -ls /tempExport
Found 1 items
-rw-r--r-- Z U U 1 mapr mapr 108221 2015-10-01 23:02 268435456 /tempExport/part0
p 2049.184.918810 hostname:5660
0 2180.39.131304 hostname:5660
[user@hostname ~]$ mapr importtable -src /tempExport/* -dst /new_collection/artworks
Header: hostName: hostname, Time Zone: Pacific Standard Time, processName: null, processId: null
2015-10-01 23:04:50,022 INFO org.apache.hadoop.io.compress.zlib.ZlibFactory <clinit> pool-1-thread-1: Successfully loaded & initialized native-zlib library
2015-10-01 23:04:50,029 INFO org.apache.hadoop.io.compress.CodecPool getDecompressor pool-1-thread-1: Got brand-new decompressor [.deflate]
[user@hostname ~]$