Listing Column Families

You can view the column families for a table using MCS and the CLI.

Viewing Table Column Families Using MCS

To view the column families for a table:
  1. Go to the table information page.
  2. Click Column Families.
    The page displays the default permissions for the column families in the Default Column Family Authorization pane and for each column family, the All pane displays:
    Column Name Column Description
    Column Family Name The name of the column family.
    JSON Path The JSON path for the column in the JSON file in dotted notation.
    Compression The compression scheme used for the column family.
    Time-to-Live The amount of time to keep the data in the column family.
    In Memory Whether or not this column value resides in memory.
    Selecting the checkbox associated with the column family makes the Remove Column Family button available. You can:
    • Add a column family to the table
    • Remove a column family associated with the table

Viewing Table Column Families Using the CLI or REST API

The command to list the column families that are in a table is:
maprcli table cf list -path <path> -cfname <name_of_column_family>

The format of the value of the -path parameter depends on whether you are viewing 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
To run this command, your user ID must have the following permissions:
  • readAce on the volume
  • lookupdir on directories in the paths
  • adminaccessperm on the table

For complete reference, see table cf list.