pg_incremental is a simple extension that helps you do fast, reliable,
incremental batch processing in PostgreSQL.

With pg_incremental, you define a pipeline with a parameterized query. The
pipeline is executed for all existing data when created, and then periodically
executed. If there is new data, the query is executed with parameter values that
correspond to the new data. Depending on the type of pipeline, the parameters
could reflect a new range of sequence values, a new time range, or a new file.