Workshop software upgraded Sisense recently (first week March 2021), and the new version refused to read all the PostGres data from a 12M row table. It would stop after 2-4M rows with no error. The fix from Sisense themselves was
Admin -> System Management -> Configuration (opens new tab) -> Scroll to bottom -> Click Manage Connectors -> Menu on Left appears with Connectors -> PostgreSQL -> Set Enabled to off
This still enables PostGres to work and it pulls all the records as expected.