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

Teradata Vantageā„¢ - Native Object Store Getting Started Guide

Product
Advanced SQL Engine
Teradata Database
Release Number
17.05
Release Date
January 2021
Content Type
Programming Reference
Publication ID
B035-1214-175K
Language
English (United States)

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