Re: Hibernate, web application and only one sequence for all primary keys
От | rawi |
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Тема | Re: Hibernate, web application and only one sequence for all primary keys |
Дата | |
Msg-id | 25491924.post@talk.nabble.com обсуждение исходный текст |
Ответ на | Re: Hibernate, web application and only one sequence for all primary keys (Leo Mannhart <leo.mannhart@beecom.ch>) |
Ответы |
Re: Hibernate, web application and only one sequence for all
primary keys
Re: Hibernate, web application and only one sequence for all primary keys Re: Hibernate, web application and only one sequence for all primary keys |
Список | pgsql-sql |
Leo Mannhart wrote: > > Caveat: If you use the standard sequence generator in hibernate, it is > not using the postgres-sequence in the "usual" manner. hibernate itself > caches 50 ID's as sequence numbers by default. This means, hibernate > only does a select on the database sequence every 50 numbers. it > multyplies the database sequence by 50 to get the "real" sequence > number. it generates the sequence numbers in blocks of 50 numbers or > according to the sequence cache size. > That said, you would probably not see any performance bottlenecks > because of the sequence number generator in the database, even with > thousands of inserts per second. > Hi Leo, thank you for the explanation! I don't know if it is that cool to lose up to 50 IDs on each session-end of Hibernate... And what do you suppose it would happen, if I set the cache size of Hibernate's own sequence (after generation) by hand to 1 instead of 50? I wouldn't need tausends of inserts per second... Kind regards, Rawi -- View this message in context: http://www.nabble.com/Hibernate%2C-web-application-and-only-one-sequence-for-all-primary-keys-tp25490498p25491924.html Sent from the PostgreSQL - sql mailing list archive at Nabble.com.
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