Add query derivation for delete queries [DATAJDBC-551]

rod2j opened DATAJDBC-551 and commented

Derived delete/removeByXxx queries work as expected for return type void but fail when return type is long/Long or List<entity type>, where it should return the number of records or the list of entities actually deleted:

instead I get

org.springframework.aop.AopInvocationException: Null return value from advice does not match primitive return type for: public abstract long 

it also appears the generated SQL query is actually a SELECT instead of a DELETE whenever the derived delete query has a non void return type.

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Affects: 2.0 GA (Neumann)

Issue Links:

• DATAJDBC-568 Derived delete query throws IncorrectResultSetColumnCountException (“is duplicated by”)

Referenced from: pull request https://github.com/spring-projects/spring-data-jdbc/pull/230

2 votes, 7 watchers

[spring-projects-issues]

Mark Paluch commented

Thanks for reporting the issue. Derived delete queries are not yet supported

[spring-projects-issues]

Rob Maskell commented

I tried a derived delete query with a void return type and this exception was thrown

org.springframework.data.mapping.model.MappingInstantiationException: Failed to instantiate void using constructor NO_CONSTRUCTOR with arguments 

The repository method signature was

void deleteByEventId(Long eventId);