To use NOS, create a foreign table definition inside Advanced SQL Engine, point it at any external object store you are authorized to access, and then you can explore the data using all the analytics ability of Teradata Vantage. The NOS table definition is called a foreign table. A foreign table makes the external data available in a structured relational format, allowing it to be aggregated or joined to other relational tables inside the database.
Data read through a foreign server is not automatically stored in the database and the data can only be seen by that query. Data can be loaded into the database using the techniques shown in Loading External Data into the Database.
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.
- To run NOS-related commands, log on to the database as a user with the required privileges.
- Create the foreign table or ask your database administrator to create the foreign table that is used by the Teradata-supplied examples. You can create it without specifying the data columns of the data (and let NOS discover the schema) or you can specify the data columns:
Create the foreign table and let NOS figure out the schema of the data:
CREATE FOREIGN TABLE table_name , EXTERNAL SECURITY authorization_object USING (LOCATION('YOUR-OBJECT-STORE-URI'));
See Variable Substitutions for Examples for the credentials and location values for the sample river flow data set.
Example: Setting Up to Run Examples
If the authorization object does not exist, create it or ask your database administrator to create it. See Variable Substitutions for Examples.
CREATE FOREIGN TABLE riverflow , EXTERNAL SECURITY MyAuthObj USING (LOCATION('/s3/td-usgs-public.s3.amazonaws.com/CSVDATA/') );
For other data formats, the sample URIs are shown in the "YOUR-OBJECT-STORE-URI" section of Variable Substitutions for Examples.