View the Key Structure | Native Object Store ( NOS ) | Teradata Vantage - 17.05 - Viewing the Key Structure - Teradata Database

Teradata Vantageā„¢ - Native Object Store Getting Started Guide

prodname
Advanced SQL Engine
Teradata Database
vrm_release
17.05
created_date
January 2021
category
Programming Reference
featnum
B035-1214-175K

Parquet data stored on an external object store has two parts: a key (path) and an object that contains a set of columns.

Key
A key prefix that identifies a set of objects to be enumerated. Given the key structure of the td-usgs bucket, which contains United States Geological Survey river flow data data / siteno / year / month / day, an example key is /S3/td-usgs.s3.amazonaws.com/CSVDATA/09380000/2018/07.
Object
The object contains the data stored in a columnar format.

The examples and results show a sample river flow data set. To use your own data, replace the table and column names, and authorization object.

  1. To run NOS-related commands, log on to the database as a user with the required privileges.
  2. View the key structure of Parquet data by selecting its LOCATION value from READ_NOS:
    SELECT TOP 2 LOCATION FROM READ_NOS_FM (
    USING
    RETURNTYPE ('NOSREAD_KEYS')
    LOCATION('YOUR-STORAGE-ACCOUNT')
    ) AS D;

    See Variable Substitutions for Examples for the credentials and location values for the sample river flow data set.

    Your result will be similar to this, reflecting your external object store location:

    Location
    --------------------------------------------------------------------
    /S3/td-usgs.s3.amazonaws.com/PARQUETDATA/09394500/2018/06/27.parquet
    /S3/td-usgs.s3.amazonaws.com/PARQUETDATA/09394500/2018/07/01.parquet