QueryEngine — Local

Source: reventless-local/src/adapter/QueryEngine/LocalQueryEngine.res

AWS equivalent: QueryEngine → DynamoDB

How It Works

Created via Make(Bus) functor. Uses the bus's QueryDb registries to look up data:

• scan — calls Bus.getQueryDbStream(readModelName) and applies Stream.take(limit) to honour the limit without loading all items. Falls back to Bus.getQueryDbScan for backward compatibility.
• query — calls Bus.getQueryDb(readModelName) to get the operations record, then uses loadStream with optional Stream.take(limit).

Operations

Operation	Description
scan	Full scan of a read model's data with optional limit
query	Key-based lookup with optional limit

Key Differences from AWS

Aspect	Local	AWS
Scan	In-memory array/stream iteration	DynamoDB Scan with filter expressions
Query	Dict key lookup	DynamoDB Query with key conditions
Indexes	Not supported	secondary index/LSI support
Filtering	None (returns all matches)	DynamoDB filter expressions