Introduced pessimistic locks for derived queries.

[DiegoKrupitza]

Methods which use the derive query functionality now can be annotated with @Lock to used a given LockMode. Right now there are two different modes PESSIMISTIC_READ and PESSIMISTIC_WRITE. Based on the dialect the right select is generated. For example for HSQLDB Select ... FOR UPDATE.

Related tickets #1041

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[schauder]

Thanks for the PR that is polished and merged.

It does not solve #1041 since that one asked for the same thing, but for Spring Data R2DBC.
If you happen to be interested in tackling that as well, it would be highly appreciated.

[DiegoKrupitza]

Thanks for the PR that is polished and merged.

It does not solve #1041 since that one asked for the same thing, but for Spring Data R2DBC.

Oh ok I don't know why I thought that 😅 . I am quite confused why is this issue then in the spring-data-jpa and not Spring Data R2DBC?

If you happen to be interested in tackling that as well, it would be highly appreciated.

If I find time for it I will take a closer look at it, but my R2DBC knowledge is quite limited...

@schauder

[schauder]

I am quite confused why is this issue then in the spring-data-jpa and not Spring Data R2DBC?

Well it's in spring-data-jdbc not spring-data-jpa 😂

Since both modules spring-data-jdbc and spring-data-r2dbc rely on spring-data-relational which is an artifact build from the spring-data-jdbc repository, it gets easy to get confused.

In the not to far future spring-data-jdbc and spring-data-r2dbc will get moved into one repository.
I'm not sure though if this will be helpful on the confusion front.

[DiegoKrupitza]

Well it's in spring-data-jdbc not spring-data-jpa 😂

Yeah I wrote spring-data-jpa by mistake 😂

In the not to far future spring-data-jdbc and spring-data-r2dbc will get moved into one repository. I'm not sure though if this will be helpful on the confusion front.

I think this won't make it better 😅 because when I hear "r2dbc" I instantly think about "reactive" and when I hear "jdbc" the last thing that comes to my mind is "reactive" 😅 , but maybe with clear documentation this should not be a problem

[schauder]

when I hear "r2dbc" I instantly think about "reactive" and when I hear "jdbc" the last thing that comes to my mind is "reactive"

And that is absolutely correct. But both use SQL to access relational databases, so they already have a lot in common and in the future will share even more code.

[DiegoKrupitza]

It does not solve #1041 since that one asked for the same thing, but for Spring Data R2DBC.
@schauder

This should now be implemented with spring-projects/spring-data-r2dbc#720