Here are some known issues, limitations, and things to be aware of. Should any of these issues get in your way, please let us know right away.

Application

It's not possible to see per-stream input metrics in the app, only aggregate metrics.

API

Pagination query parameters are ignored in List APIs (eg: GET /pipelines, /streams, /connections).

Custom stream retention settings are not yet user-facing. For now, contact support if you need help adjusting stream retention.

Common Table Expressions (CTEs) are not currently supported.
SQL has a large number of reserved words. To use a reserved keyword as a column, table, or similar identifier, use backticks (e.g. `reserved-word`) to quote it.
Expressions in a select that aren't explicitly given a name will be given a generated column name such as EXPR$1. Use the as keyword to provide a name (e.g. select 2 + 2 as hopefully_four ..., select to_timestamp(ts) as ts ...).
When performing windowed aggregation, you must group by both the generated window_start and window_end fields.
Sliding windows (i.e. the hop() function) require the size argument to be a multiple of the slide interval. As an example, hop(table x, descriptor(ts), interval '1' second, interval '60' seconds) is valid while hop(table x, descriptor(ts), interval '3' seconds, interval '5' seconds) is not).
Session windows are not currently available.