Repository and Pull Request deletion fails due to Database error

2017-05-23 13:24:27,326 WARN  [http-nio-7990-exec-8] admin @1S1B560x804x86x0 ohu5hs 0:0:0:0:0:0:0:1 "DELETE /projects/AWESOMEFROZENSALAD35194/repos/linux HTTP/1.1" o.h.e.jdbc.spi.SqlExceptionHelper SQL Error: 23503, SQLState: 23503
2017-05-23 13:24:27,327 ERROR [http-nio-7990-exec-8] admin @1S1B560x804x86x0 ohu5hs 0:0:0:0:0:0:0:1 "DELETE /projects/AWESOMEFROZENSALAD35194/repos/linux HTTP/1.1" o.h.e.jdbc.spi.SqlExceptionHelper Referential integrity constraint violation: "FK_STA_PR_DIFF_COM_ANC_PR: PUBLIC.STA_PR_DIFF_COMMENT_ANCHOR FOREIGN KEY(PR_ID) REFERENCES PUBLIC.STA_PULL_REQUEST(ID) (1)"; SQL statement:
delete from sta_pull_request where to_repository_id=? [23503-176]
2017-05-23 13:24:27,335 ERROR [http-nio-7990-exec-8] admin @1S1B560x804x86x0 ohu5hs 0:0:0:0:0:0:0:1 "DELETE /projects/AWESOMEFROZENSALAD35194/repos/linux HTTP/1.1" c.a.s.i.p.DefaultPullRequestService AWESOMEFROZENSALAD35194/linux[16]: Pull requests could not be cleaned up on repository deletion
org.hibernate.exception.ConstraintViolationException: could not execute statement
	at org.hibernate.exception.internal.SQLStateConversionDelegate.convert(SQLStateConversionDelegate.java:112)
	at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter.java:42)
	at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:111)
	at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:97)
	at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.executeUpdate(ResultSetReturnImpl.java:208)
	at org.hibernate.hql.internal.ast.exec.BasicExecutor.doExecute(BasicExecutor.java:90)
	at org.hibernate.hql.internal.ast.exec.BasicExecutor.execute(BasicExecutor.java:59)
	at org.hibernate.hql.internal.ast.exec.DeleteExecutor.execute(DeleteExecutor.java:110)
	at org.hibernate.hql.internal.ast.QueryTranslatorImpl.executeUpdate(QueryTranslatorImpl.java:437)
	at org.hibernate.engine.query.spi.HQLQueryPlan.performExecuteUpdate(HQLQueryPlan.java:374)
	at org.hibernate.internal.SessionImpl.executeUpdate(SessionImpl.java:1510)
	at org.hibernate.query.internal.AbstractProducedQuery.doExecuteUpdate(AbstractProducedQuery.java:1526)
	at org.hibernate.query.internal.AbstractProducedQuery.executeUpdate(AbstractProducedQuery.java:1504)
	at com.atlassian.stash.internal.pull.HibernatePullRequestDao.deleteByToRepository(HibernatePullRequestDao.java:183)
	at com.atlassian.stash.internal.pull.DefaultPullRequestService.cleanup(DefaultPullRequestService.java:1231)
	at com.atlassian.stash.internal.pull.DefaultPullRequestService.onRepositoryDeleteRequested(DefaultPullRequestService.java:684)
	at com.atlassian.event.internal.SingleParameterMethodListenerInvoker.invoke(SingleParameterMethodListenerInvoker.java:40)
	at com.atlassian.event.internal.AsynchronousAbleEventDispatcher$1$1.run(AsynchronousAbleEventDispatcher.java:38)
	at com.google.common.util.concurrent.MoreExecutors$DirectExecutor.execute(MoreExecutors.java:457)
	at com.atlassian.event.internal.AsynchronousAbleEventDispatcher.dispatch(AsynchronousAbleEventDispatcher.java:88)
	at com.atlassian.event.internal.LockFreeEventPublisher$Publisher.dispatch(LockFreeEventPublisher.java:222)
	at com.atlassian.event.internal.LockFreeEventPublisher.publish(LockFreeEventPublisher.java:95)
	at com.atlassian.stash.internal.event.TransactionAwareEventPublisher.internalPublish(TransactionAwareEventPublisher.java:155)
	at com.atlassian.stash.internal.event.TransactionAwareEventPublisher.publish(TransactionAwareEventPublisher.java:99)
	at com.atlassian.stash.internal.repository.DefaultRepositoryService.fireRepositoryDeletionRequested(DefaultRepositoryService.java:711)
	at com.atlassian.stash.internal.repository.DefaultRepositoryService.lambda$delete$1(DefaultRepositoryService.java:186)
	at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:133)
	at com.atlassian.stash.internal.repository.DefaultRepositoryService.delete(DefaultRepositoryService.java:185)
	at com.atlassian.plugin.util.ContextClassLoaderSettingInvocationHandler.invoke(ContextClassLoaderSettingInvocationHandler.java:26)
	at org.eclipse.gemini.blueprint.service.importer.support.internal.aop.ServiceInvoker.doInvoke(ServiceInvoker.java:56)
	at org.eclipse.gemini.blueprint.service.importer.support.internal.aop.ServiceInvoker.invoke(ServiceInvoker.java:60)
	at org.eclipse.gemini.blueprint.service.util.internal.aop.ServiceTCCLInterceptor.invokeUnprivileged(ServiceTCCLInterceptor.java:70)
	at org.eclipse.gemini.blueprint.service.util.internal.aop.ServiceTCCLInterceptor.invoke(ServiceTCCLInterceptor.java:53)
	at org.eclipse.gemini.blueprint.service.importer.support.LocalBundleContextAdvice.invoke(LocalBundleContextAdvice.java:57)
	at com.atlassian.stash.internal.rest.repository.RepositoryResource.deleteRepository(RepositoryResource.java:168)
	at com.atlassian.applinks.core.rest.context.ContextFilter.doFilter(ContextFilter.java:24)
	at com.atlassian.applinks.core.rest.context.ContextFilter.doFilter(ContextFilter.java:24)
	at com.atlassian.applinks.core.rest.context.ContextFilter.doFilter(ContextFilter.java:24)
	at com.atlassian.applinks.core.rest.context.ContextFilter.doFilter(ContextFilter.java:24)
	at com.atlassian.applinks.core.rest.context.ContextFilter.doFilter(ContextFilter.java:24)
	at com.atlassian.stash.internal.spring.lifecycle.LifecycleJohnsonServletFilterModuleContainerFilter.doFilter(LifecycleJohnsonServletFilterModuleContainerFilter.java:42)
	at com.atlassian.stash.internal.spring.lifecycle.LifecycleJohnsonServletFilterModuleContainerFilter.doFilter(LifecycleJohnsonServletFilterModuleContainerFilter.java:42)
	at com.atlassian.stash.internal.spring.security.StashAuthenticationFilter.doFilter(StashAuthenticationFilter.java:88)
	at com.atlassian.stash.internal.web.auth.BeforeLoginPluginAuthenticationFilter.doInsideSpringSecurityChain(BeforeLoginPluginAuthenticationFilter.java:112)
	at com.atlassian.stash.internal.web.auth.BeforeLoginPluginAuthenticationFilter.doFilter(BeforeLoginPluginAuthenticationFilter.java:75)
	at com.atlassian.security.auth.trustedapps.filter.TrustedApplicationsFilter.doFilter(TrustedApplicationsFilter.java:94)
	at com.atlassian.oauth.serviceprovider.internal.servlet.OAuthFilter.doFilter(OAuthFilter.java:67)
	at com.atlassian.stash.internal.spring.lifecycle.LifecycleJohnsonServletFilterModuleContainerFilter.doFilter(LifecycleJohnsonServletFilterModuleContainerFilter.java:42)
	at com.atlassian.stash.internal.spring.lifecycle.LifecycleJohnsonServletFilterModuleContainerFilter.doFilter(LifecycleJohnsonServletFilterModuleContainerFilter.java:42)
	at com.atlassian.security.auth.trustedapps.filter.TrustedApplicationsFilter.doFilter(TrustedApplicationsFilter.java:94)
	at com.atlassian.oauth.serviceprovider.internal.servlet.OAuthFilter.doFilter(OAuthFilter.java:67)
	at com.atlassian.stash.internal.spring.lifecycle.LifecycleJohnsonServletFilterModuleContainerFilter.doFilter(LifecycleJohnsonServletFilterModuleContainerFilter.java:42)
	at com.atlassian.plugin.connect.plugin.auth.user.ThreeLeggedAuthFilter.doFilter(ThreeLeggedAuthFilter.java:109)
	at com.atlassian.jwt.internal.servlet.JwtAuthFilter.doFilter(JwtAuthFilter.java:32)
	at com.atlassian.analytics.client.filter.DefaultAnalyticsFilter.doFilter(DefaultAnalyticsFilter.java:38)
	at com.atlassian.analytics.client.filter.AbstractHttpFilter.doFilter(AbstractHttpFilter.java:39)
	at com.atlassian.stash.internal.spring.lifecycle.LifecycleJohnsonServletFilterModuleContainerFilter.doFilter(LifecycleJohnsonServletFilterModuleContainerFilter.java:42)
	at com.atlassian.stash.internal.web.auth.BeforeLoginPluginAuthenticationFilter.doBeforeBeforeLoginFilters(BeforeLoginPluginAuthenticationFilter.java:90)
	at com.atlassian.stash.internal.web.auth.BeforeLoginPluginAuthenticationFilter.doFilter(BeforeLoginPluginAuthenticationFilter.java:73)
	at com.atlassian.stash.internal.request.DefaultRequestManager.doAsRequest(DefaultRequestManager.java:89)
	at com.atlassian.stash.internal.hazelcast.ConfigurableWebFilter.doFilter(ConfigurableWebFilter.java:38)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.lang.Thread.run(Thread.java:745)
	... 344 frames trimmed
Caused by: org.h2.jdbc.JdbcSQLException: Referential integrity constraint violation: "FK_STA_PR_DIFF_COM_ANC_PR: PUBLIC.STA_PR_DIFF_COMMENT_ANCHOR FOREIGN KEY(PR_ID) REFERENCES PUBLIC.STA_PULL_REQUEST(ID) (1)"; SQL statement:
delete from sta_pull_request where to_repository_id=? [23503-176]
	at org.h2.message.DbException.getJdbcSQLException(DbException.java:344)
	at org.h2.message.DbException.get(DbException.java:178)
	at org.h2.message.DbException.get(DbException.java:154)
	at org.h2.constraint.ConstraintReferential.checkRow(ConstraintReferential.java:427)
	at org.h2.constraint.ConstraintReferential.checkRowRefTable(ConstraintReferential.java:444)
	at org.h2.constraint.ConstraintReferential.checkRow(ConstraintReferential.java:319)
	at org.h2.table.Table.fireConstraints(Table.java:909)
	at org.h2.table.Table.fireAfterRow(Table.java:927)
	at org.h2.command.dml.Delete.update(Delete.java:101)
	at org.h2.command.CommandContainer.update(CommandContainer.java:79)
	at org.h2.command.Command.executeUpdate(Command.java:254)
	at org.h2.jdbc.JdbcPreparedStatement.executeUpdateInternal(JdbcPreparedStatement.java:158)
	at org.h2.jdbc.JdbcPreparedStatement.executeUpdate(JdbcPreparedStatement.java:144)
	at com.zaxxer.hikari.pool.ProxyPreparedStatement.executeUpdate(ProxyPreparedStatement.java:61)
	at com.zaxxer.hikari.pool.HikariProxyPreparedStatement.executeUpdate(HikariProxyPreparedStatement.java)
	at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.executeUpdate(ResultSetReturnImpl.java:205)
	... 59 common frames omitted