Configure Sampling and Profiling

Alation Cloud Service Applies to Alation Cloud Service instances of Alation

Customer Managed Applies to customer-managed instances of Alation

Refer to Configure Sampling and Profiling for OCF Data Sources.


Google BigQuery allows you to create tables using the require_partition_filter feature. This feature will enable you to run simple queries on the table only if you use a filter over the partition column. However, Alation uses simple queries to fetch the sample values of the struct column during table sampling without using a filter, causing the table sampling to fail.

To workaround this issue, change the default query to a custom query during custom table sampling. Custom query allows you to use a filter over the partition column.