Question

我的Postgres版本是9.6.12。当我运行以下查询时，Postgres崩溃并显示以下错误。当我仅用JOIN替换LEFT JOIN时，查询工作正常

proddb=# SELECT 1 - count(event_date) AS result FROM (SELECT now()::date AS run_date) p 
JOIN historic.audit_event ON event_code = 5199
 AND event_param1 = 'fullscriptpendingorders' AND event_date > run_date 
AND event_date < (run_date + '1 day'::interval);
 result
--------
      0
(1 row)

-- When I change the JOIN to LEFT JOIN
proddb=# SELECT 1 - count(event_date) AS result FROM (SELECT now()::date AS run_date) p
**LEFT JOIN** historic.audit_event ON event_code = 5199 
AND event_param1 = 'fullscriptpendingorders' 
AND event_date > run_date 
AND event_date < (run_date + '1 day'::interval);
server closed the connection unexpectedly
        This probably means the server terminated abnormally
        before or while processing the request.
The connection to the server was lost. Attempting reset: Failed.

postgres日志显示以下错误，表明Postgres崩溃了。几分钟后，Postgres会自动恢复，但这会影响关键的生产。你能帮忙吗？这是Postgres的错误吗？

2019-04-08 21:32:56 PDT [26911]: [19631-1] [] [] LOG:  00000: server process (PID 23981) was terminated by signal 11: Segmentation fault
2019-04-08 21:32:56 PDT [26911]: [19632-1] [] [] DETAIL:  Failed process was running: SELECT 1 - count(event_date) AS result FROM (SELECT now()::date AS run_date) p LEFT JOIN historic.audit_event ON event_code = 5199 AND event_param1 = 'amsa.fullscriptpendingorders' AND event_date > run_date AND event_date < (run_date + '1 day'::interval);
2019-04-08 21:32:56 PDT [26911]: [19633-1] [] [] LOCATION:  LogChildExit, postmaster.c:3574
2019-04-08 21:32:56 PDT [26911]: [19634-1] [] [] LOG:  00000: terminating any other active server processes
2019-04-08 21:32:56 PDT [26911]: [19635-1] [] [] LOCATION:  HandleChildCrash, postmaster.c:3294
2019-04-08 21:32:56 PDT [24633]: [1-1] [[unknown]] [[unknown]] LOG:  00000: connection received: host=[local]
2019-04-08 21:32:56 PDT [24633]: [2-1] [[unknown]] [[unknown]] LOCATION:  BackendInitialize, postmaster.c:4192
2019-04-08 21:32:56 PDT [24633]: [3-1] [postgres] [emr_prod] FATAL:  57P03: the database system is in recovery mode
2019-04-08 21:32:56 PDT [24633]: [4-1] [postgres] [emr_prod] LOCATION:  ProcessStartupPacket, postmaster.c:2230
2019-04-08 21:32:56 PDT [26911]: [19636-1] [] [] LOG:  00000: all server processes terminated; reinitializing
2019-04-08 21:32:56 PDT [26911]: [19637-1] [] [] LOCATION:  PostmasterStateMachine, postmaster.c:3818

当我在版本9.6.9的QA数据库上拥有确切的数据集时，我没有看到此行为

postgres@emr_qa07=# select version();
                                                 version
----------------------------------------------------------------------------------------------------------
 PostgreSQL 9.6.9 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-16), 64-bit
(1 row)

postgres@emr_qa07=# SELECT 1 - count(event_date) AS result FROM (SELECT now()::date AS run_date) p JOIN historic.audit_event ON event_code = 5199 AND event_param1 = 'fullscriptpendingorders' AND event_date > run_date AND event_date < (run_date + '1 day'::interval);
 result
--------
      1
(1 row)

postgres@emr_qa07=# SELECT 1 - count(event_date) AS result FROM (SELECT now()::date AS run_date) p LEFT JOIN historic.audit_event ON event_code = 5199 AND event_param1 = 'fullscriptpendingorders' AND event_date > run_date AND event_date < (run_date + '1 day'::interval);
 result
--------
      1
(1 row)

Answer 1

是的，这是PostgreSQL的错误-不管您提供什么查询，都绝不应该进行段错误。如果您可以将其减少到最小的测试用例，则开发人员可能会对错误报告感兴趣。

这里的另一种可能性是数据库的基础数据文件已损坏。 PostgreSQL仍然是一个崩溃的错误，但是要确定发生了什么将更加困难。潜在地转储和还原数据库可能会修复它。

使用LEFT JOIN时，Postgres因分段错误而崩溃

1 个答案: