PostgreSQL 9.6 Parallel Units

Question

PostgreSQL in version 9.6 adds support for parallel aggregates.

With 9.6, PostgreSQL introduces initial support for parallel execution of large queries. Only read-only queries in which access to the table through sequential scanning can be parallelized. union hashes and nested loops can be performed in parallel, aggregation (for supported aggregates). Much remains to be done, but this is already a useful feature set.

• What are the supported units mentioned above?
• Are there any special considerations when developing aggregate functions that allow the use of parallel mechanisms?

Answer 1

PostgreSQL 9.6 , , :

35.10.4.

, . , , , , . . , . ( ; .)

, , type ( ) , . , . , .