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SAP / olingo-jpa-processor-v4

The JPA Processor fills the gap between Olingo V4 and the database, by providing a mapping between JPA metadata and OData metadata, generating queries and supporting the entity manipulations.
Apache License 2.0
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Is it even possible to do server side paging towards the database if ordering can not be guaranteed? #191

Closed PerArneng closed 1 year ago

PerArneng commented 1 year ago

The example paging provider in the source repository does an offset/limit query on each page. According to ex the PostgreSQL documentation it's not recommended to do that without an order by. https://www.postgresql.org/docs/current/queries-limit.html . Is it even possible to make reliable server-side paging when the order is not guaranteed?

PerArneng commented 1 year ago

One solution that seems to work is to have database views that contain order by to ensure that there is an order

wog48 commented 1 year ago

Actually, also server driven paging shall by default create an ORDER BY primary key, as it is done for client driven paging with $top and $skip. This is a bug.

wog48 commented 1 year ago

I have created a correction. See PR https://github.com/SAP/olingo-jpa-processor-v4/pull/194.

Please try it out. In case you still face a problem, reopen the issue