Why To Avoid PostgreSQL (BIG)SERIAL In Batching Inserts Via Hibernate

Description: In PostgreSQL, using GenerationType.IDENTITY will disable insert batching. The (BIG)SERIAL is acting "almost" like MySQL, AUTO_INCREMENT. In this application, we use the GenerationType.SEQUENCE which permits insert batching, and we optimize it via the hi/lo optimization algorithm.

Key points:

• use GenerationType.SEQUENCE instead of GenerationType.IDENTITY
• rely on the hi/lo algorithm to fetch a hi value in a database roundtrip (the hi value is useful for generating a certain/given number of identifiers in-memory; until you haven't exhausted all in-memory identifiers there is no need to fetch another hi)
• you can go even further and use the Hibernate pooled and pooled-lo identifier generators (these are optimizations of hi/lo that allows external services to use the database without causing duplication keys errors)
• optimize batching via spring.datasource.hikari.data-source-properties.reWriteBatchedInserts=true

Output example:

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