The examples use a sample river flow data set. To use your own data, replace the table and column names, and authorization object. See Variable Substitutions for Examples for the credentials and location values for the sample data set.
- To run NOS-related commands, log on to the database as a user with the required privileges.
- If it does not exist, create the foreign table or ask your database administrator to create the foreign table called riverflow_parquet. See Setting Up to Run Parquet Examples.
Query for a set of rows by specifying a specific value for the site_no attribute in the command’s WHERE clause. This requests that only records with that value be returned for viewing. In this example, the max value for the Flow attribute for a single site_no is returned.
SELECT MAX(Flow) FROM riverflow_parquet WHERE site_no = '09394500';
Maximum(Flow) ------------- 232.00