Step 1. Define a column to track in a reference dataset using -record and column name
-ds reference_dataset,-rd "2019-07-15" \-q "select product_type from products" \-lib "/opt/owl/drivers/postgres/" \-cxn postgres \-record "product_types"
Step 2. Define the relationship you want to check against the reference dataset
-ds "ds1" \-rd "2018-09-26" \-q "select * from lake.orders" \-lib "/opt/owl/drivers/" \-cxn mysql \-notin "ds1&type=reference_dataset&product_types"
The inverse can be applied to check if a value is in a column by using -in instead of -notin
This is applied when there are many reference sets and several combinations for a given dataset.