The joins are very powerful. For example - you can connect a lambda function to its IAM role and then right through to the attached policies. We have quite a few join examples scattered through the AWS table docs.
For tags, Steampipe actually normalizes a tags column across AWS, Azure, GCP & DigitalOcean tables. It's always available as a JSONB {"foo":"bar"} format, even if the source was labels like DigitalOcean, so definitely possible to find resources with specific tags.
We have multi-account on the near-term roadmap, but the idea of historical searches is a super interesting and challenging idea… we haven’t started to contemplate yet. Perhaps using snapshots into a materialized view would work for comparisons over time?
