Listing Table Regions

Use a maprcli command or MCS to list the regions in which a table's data is located.

MapR-DB tables are split into regions on an ongoing basis. Administrators and developers do not need to manage these regions or restructure data on disk when data is added and deleted. These operations happen automatically. You can list region information for tables to get a sense of the size and location of table data on the MapR cluster.

maprcli command

Use the command table region list:

maprcli table region list -path <path and name of table>

The format of the value of the -path parameter depends on whether you are creating a table on a local cluster or a remote cluster:

  • For a path on the local cluster, start the path at the volume mount point. For example, for a table named test under a volume with a mount point at /volume1, specify the following path: /volume1/test
  • For a path on a remote cluster, you must also specify the cluster name in the path. For example, for a table named customer under volume1 in the sanfrancisco cluster, specify the following path:/mapr/sanfrancisco/volume1/customer

The -json parameter displays the output as a JSON document:

{
    "timestamp":1452554659812,
    "timeofday":"2016-01-11 03:24:19.812 GMT-0800",
    "status":"OK",
    "total":2,
    "data":[
        {
            "primarynode":"test150.qa.lab:5660",
            "secondarynodes":"test156.qa.lab:5661, test151.qa.lab:5660",
            "startkey":"-INFINITY",
            "endkey":"5190414F2E44DB732547630A9A81452539749000",
            "lastheartbeat":0,
            "fid":"2068.100.131676",
            "logicalsize":794624,
            "physicalsize":794624,
            "copypendingsize":0,
            "numberofrows":0,
            "numberofrowswithdelete":0,
            "numberofspills":0,
            "numberofsegments":0
        },
        {

            "primarynode":"test161.qa.lab:5660",
            "secondarynodes":"test157.qa.lab:5661, test162.qa.lab:5660",
            "startkey":"5190414F2E44DB732547630A9A81452539749000",
            "endkey":"INFINITY",
            "lastheartbeat":0,
            "fid":"2069.181.131578",
            "logicalsize":745472,
            "physicalsize":745472,
            "copypendingsize":0,
            "numberofrows":0,
            "numberofrowswithdelete":0,
            "numberofspills":0,
            "numberofsegments":0
        }
    ]
}

MCS

  1. In the MCS Navigation pane under the MapR-FS group, click Tables. The Tables section appears in the main window.
  2. Find the table you want to work with, using one of the following methods:
    • Scan for the table under Recently Opened Tables in the Tables section.
    • Enter the table pathname in the Go to table field and click Go.
  3. Click the desired table name. A Table section appears in the main MCS pane, displaying information for the specific table.
  4. Click the Regions tab. The Regions section displays region information for the table.