Pagination with JOINs for repository methods

[dstepanov]

• For repository methods with JOIN and pagenation, the query is generated as:

        // SQL tabular results with JOINs cannot be property limited by LIMIT and OFFSET
        // Create a query that can be paginated with JOINs using a subquery
        //
        // SELECT mainEntity.* FROM MyEntity mainEntity JOIN ... WHERE mainEntity.id in (
        //     SELECT paginationEntity.id FROM MyEntity paginationEntity WHERE paginationEntity.id in (
        //        SELECT filteredEntity.id FROM MyEntity filteredEntity JOIN ... WHERE ... ;
        //     ) ORDER BY ... LIMIT ... OFFSET ...
        // ) ORDER BY ...
        //

(In future version we can optimize it)

• Only valid for SQL and JPA builders - we might consider another layer between the query builder for repositories to generate queries
• The append of pagination / sort is implemented using an expandable functionality of queries.
• The count query is now represented as a separate annotation (with backwards compatibility). In the next major version I would like to change to have:
  • DataMethod - basic representation of the method
  • "queryDefinition" - eveything about the query etc
  • "countQueryDefinition" - eveything about the count query etc
  • possibly a collection of queries, we can also support different dialects for one method if needed
• Not working for MySql now, because MySql doesn't support LIMIT in subqueries. It could be implemented using a JOIN - SELECT ... JOIN (Select ... ) as filtered WHERE filtered.id = ID, but our criteria don't support this kind of query yet

[graemerocher]

does it work for cursor pagination?

[dstepanov]

I have added a test. It looks like it's working, but I found a scenario that doesn't work, which is not related to my changes. When we reach the end and find a page that returns nothing, it's impossible to go back. Any idea @andriy-dmytruk?

[sonarqubecloud]

Quality Gate failed

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1 New Bugs (required ≤ 0)
3 New Critical Issues (required ≤ 0)

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