Problem with serialization DuckDBArray

[m1hail1337]

I have a simple spring rest controller, that query into DuckDB via JDBC.
When i try query some list data (like SELECT [] as list) i have error with serialization by spring (data from DuckDB delivers correctly in debug mode).
Logs:

2025-03-21 11:13:53 DEBUG DuckDBRepository:46 - SELECT [] as list
2025-03-21 11:13:53 WARN  ExceptionHandler:30 - Handle exception: org.springframework.http.converter.HttpMessageNotWritableException
2025-03-21 11:13:53 ERROR ExceptionHandler:40 - Could not write JSON: getCursorName
org.springframework.http.converter.HttpMessageNotWritableException: Could not write JSON: getCursorName
	at org.springframework.http.converter.json.AbstractJackson2HttpMessageConverter.writeInternal(AbstractJackson2HttpMessageConverter.java:492) ~[spring-web-6.0.9.jar:6.0.9]
	at org.springframework.http.converter.AbstractGenericHttpMessageConverter.write(AbstractGenericHttpMessageConverter.java:103) ~[spring-web-6.0.9.jar:6.0.9]
	at org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodProcessor.writeWithMessageConverters(AbstractMessageConverterMethodProcessor.java:297) ~[spring-webmvc-6.0.9.jar:6.0.9]
	at org.springframework.web.servlet.mvc.method.annotation.RequestResponseBodyMethodProcessor.handleReturnValue(RequestResponseBodyMethodProcessor.java:194) ~[spring-webmvc-6.0.9.jar:6.0.9]
	at org.springframework.web.method.support.HandlerMethodReturnValueHandlerComposite.handleReturnValue(HandlerMethodReturnValueHandlerComposite.java:78) ~[spring-web-6.0.9.jar:6.0.9]
	at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:136) ~[spring-webmvc-6.0.9.jar:6.0.9]
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:884) ~[spring-webmvc-6.0.9.jar:6.0.9]
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:797) ~[spring-webmvc-6.0.9.jar:6.0.9]
	at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-6.0.9.jar:6.0.9]
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1081) ~[spring-webmvc-6.0.9.jar:6.0.9]
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:974) ~[spring-webmvc-6.0.9.jar:6.0.9]
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1011) ~[spring-webmvc-6.0.9.jar:6.0.9]
	at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:914) ~[spring-webmvc-6.0.9.jar:6.0.9]
	at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:590) ~[servlet-api.jar:6.0]
	at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:885) ~[spring-webmvc-6.0.9.jar:6.0.9]
	at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:658) ~[servlet-api.jar:6.0]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:195) ~[catalina.jar:10.1.24]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:140) ~[catalina.jar:10.1.24]
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51) ~[tomcat-websocket.jar:10.1.24]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:164) ~[catalina.jar:10.1.24]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:140) ~[catalina.jar:10.1.24]
	at org.springframework.security.web.FilterChainProxy.lambda$doFilterInternal$3(FilterChainProxy.java:231) ~[spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:365) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.access.intercept.AuthorizationFilter.doFilter(AuthorizationFilter.java:100) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:126) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:120) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:131) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:85) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:100) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.authentication.rememberme.RememberMeAuthenticationFilter.doFilter(RememberMeAuthenticationFilter.java:110) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.authentication.rememberme.RememberMeAuthenticationFilter.doFilter(RememberMeAuthenticationFilter.java:101) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:179) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:63) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) [spring-security-web-6.0.3.jar:6.0.3]
	at sentinel.system.jwt.JwtAuthorizationFilter.doFilterInternal(JwtAuthorizationFilter.java:51) [sentinel-authorization-24.8.0-JDK17-SPRING6-SNAPSHOT.jar:?]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) [spring-web-6.0.9.jar:6.0.9]
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.session.ConcurrentSessionFilter.doFilter(ConcurrentSessionFilter.java:151) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.session.ConcurrentSessionFilter.doFilter(ConcurrentSessionFilter.java:129) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:227) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:221) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:107) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:93) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.header.HeaderWriterFilter.doHeadersAfter(HeaderWriterFilter.java:90) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:75) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) [spring-web-6.0.9.jar:6.0.9]
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.context.SecurityContextHolderFilter.doFilter(SecurityContextHolderFilter.java:82) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.context.SecurityContextHolderFilter.doFilter(SecurityContextHolderFilter.java:69) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:62) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) [spring-web-6.0.9.jar:6.0.9]
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.session.DisableEncodeUrlFilter.doFilterInternal(DisableEncodeUrlFilter.java:42) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) [spring-web-6.0.9.jar:6.0.9]
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:233) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:191) [spring-security-web-6.0.3.jar:6.0.3]
	at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:352) [spring-web-6.0.9.jar:6.0.9]
	at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:268) [spring-web-6.0.9.jar:6.0.9]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:164) [catalina.jar:10.1.24]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:140) [catalina.jar:10.1.24]
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) [spring-web-6.0.9.jar:6.0.9]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) [spring-web-6.0.9.jar:6.0.9]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:164) [catalina.jar:10.1.24]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:140) [catalina.jar:10.1.24]
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:167) [catalina.jar:10.1.24]
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:90) [catalina.jar:10.1.24]
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:482) [catalina.jar:10.1.24]
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:115) [catalina.jar:10.1.24]
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:93) [catalina.jar:10.1.24]
	at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:663) [catalina.jar:10.1.24]
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) [catalina.jar:10.1.24]
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:344) [catalina.jar:10.1.24]
	at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:389) [tomcat-coyote.jar:10.1.24]
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:63) [tomcat-coyote.jar:10.1.24]
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:896) [tomcat-coyote.jar:10.1.24]
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1741) [tomcat-coyote.jar:10.1.24]
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:52) [tomcat-coyote.jar:10.1.24]
	at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1190) [tomcat-util.jar:10.1.24]
	at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659) [tomcat-util.jar:10.1.24]
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:63) [tomcat-util.jar:10.1.24]
	at java.base/java.lang.Thread.run(Thread.java:840) [?:?]
Caused by: com.fasterxml.jackson.databind.JsonMappingException: getCursorName (through reference chain: java.util.ArrayList[0]->org.duckdb.DuckDBArray[0]->org.duckdb.DuckDBArray["resultSet"]->org.duckdb.DuckDBArrayResultSet["cursorName"])
	at com.fasterxml.jackson.databind.JsonMappingException.wrapWithPath(JsonMappingException.java:402) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.JsonMappingException.wrapWithPath(JsonMappingException.java:361) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.std.StdSerializer.wrapAndThrow(StdSerializer.java:323) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:778) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:183) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:732) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:770) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:183) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.std.ObjectArraySerializer.serializeContents(ObjectArraySerializer.java:253) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.std.ObjectArraySerializer.serialize(ObjectArraySerializer.java:214) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.std.ObjectArraySerializer.serialize(ObjectArraySerializer.java:23) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.std.CollectionSerializer.serializeContentsUsing(CollectionSerializer.java:171) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.std.CollectionSerializer.serializeContents(CollectionSerializer.java:116) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.std.CollectionSerializer.serialize(CollectionSerializer.java:107) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.std.CollectionSerializer.serialize(CollectionSerializer.java:25) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.DefaultSerializerProvider._serialize(DefaultSerializerProvider.java:502) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.DefaultSerializerProvider.serializeValue(DefaultSerializerProvider.java:422) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ObjectWriter$Prefetch.serialize(ObjectWriter.java:1570) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ObjectWriter.writeValue(ObjectWriter.java:1061) ~[jackson-databind-2.17.0.jar:2.17.0]
	at org.springframework.http.converter.json.AbstractJackson2HttpMessageConverter.writeInternal(AbstractJackson2HttpMessageConverter.java:483) ~[spring-web-6.0.9.jar:6.0.9]
	... 93 more
Caused by: java.sql.SQLFeatureNotSupportedException: getCursorName
	at org.duckdb.DuckDBArrayResultSet.getCursorName(DuckDBArrayResultSet.java:242) ~[duckdb_jdbc-1.0.0.jar:?]
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:?]
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77) ~[?:?]
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:?]
	at java.base/java.lang.reflect.Method.invoke(Method.java:569) ~[?:?]
	at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:688) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:770) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:183) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:732) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:770) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:183) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.std.ObjectArraySerializer.serializeContents(ObjectArraySerializer.java:253) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.std.ObjectArraySerializer.serialize(ObjectArraySerializer.java:214) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.std.ObjectArraySerializer.serialize(ObjectArraySerializer.java:23) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.std.CollectionSerializer.serializeContentsUsing(CollectionSerializer.java:171) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.std.CollectionSerializer.serializeContents(CollectionSerializer.java:116) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.std.CollectionSerializer.serialize(CollectionSerializer.java:107) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.std.CollectionSerializer.serialize(CollectionSerializer.java:25) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.DefaultSerializerProvider._serialize(DefaultSerializerProvider.java:502) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ser.DefaultSerializerProvider.serializeValue(DefaultSerializerProvider.java:422) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ObjectWriter$Prefetch.serialize(ObjectWriter.java:1570) ~[jackson-databind-2.17.0.jar:2.17.0]
	at com.fasterxml.jackson.databind.ObjectWriter.writeValue(ObjectWriter.java:1061) ~[jackson-databind-2.17.0.jar:2.17.0]
	at org.springframework.http.converter.json.AbstractJackson2HttpMessageConverter.writeInternal(AbstractJackson2HttpMessageConverter.java:483) ~[spring-web-6.0.9.jar:6.0.9]
	... 93 more

For some reason ObjectMapper tries to serialize result set reference in DuckDBArray. Is any ways to avoid it? Ideas?

[staticlibs]

Hi, thanks for the report! It appeared that Jackson serializer does not support java.sql.Array so, instead of calling getArray(), it tries to serialize DuckDBArray as a POJO using its public getters (including getResultSet()).

This can be solved by using custom Jackson serializer for DuckDBArray class like this:

    public class DuckDBArraySerializer extends StdSerializer<DuckDBArray> {
        protected DuckDBArraySerializer(Class<DuckDBArray> t) {
            super(t);
        }

        @Override
        public void serialize(DuckDBArray value, JsonGenerator gen, SerializerProvider provider) throws IOException {
            try {
                gen.writeStartArray();
                for(Object obj : (Object[]) value.getArray()) {
                    gen.writeObject(obj);
                }
                gen.writeEndArray();
            } catch (SQLException e) {
                throw new IOException(e);
            }
        }
    }

See full runnable example in this repo.

[m1hail1337]

@staticlibs Thanks for reply!
I solved this issue using custom serializer like you mentioned.
But is a good way to solve it? 🤔

[staticlibs]

Depending on a query, it may be better not to return ARRAY to client but to use unnest to convert it into a relational set of rows that can be returned as a normal result set.

[staticlibs]

Closing this issue assuming Jackson serializer has helped, please reopen if necessary.