PostgreSQL 12 разделов присоединяются медленные запросы - PullRequest
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PostgreSQL 12 разделов присоединяются медленные запросы

0 голосов
/ 10 апреля 2020

У меня проблема с медленным запросом при соединении двух секционированных таблиц. Этот запрос используется для проверки скорости: 

EXPLAIN (ANALYZE, COSTS, VERBOSE, BUFFERS, FORMAT JSON)
SELECT COUNT(*) AS erc_full_count
FROM event_record AS erc
      LEFT OUTER JOIN ( SELECT id, event_record_id FROM rlc_data AS rld
      WHERE rld.active is true and rld.deleted is FALSE
      AND  (NULL::BOOLEAN is NULL OR rld.group_event=NULL::BOOLEAN)
      AND (NULL::TIMESTAMP IS NULL OR rld.created_time >= NULL::TIMESTAMP)
      AND (NULL::TIMESTAMP IS NULL OR rld.created_time <= NULL::TIMESTAMP)
) AS sub_rld
ON erc.id = sub_rld.event_record_id
 WHERE erc.deleted is FALSE
 AND (-1::BIGINT = -1 OR erc.device_id=-1::BIGINT)
 AND (-1::BIGINT = -1 OR erc.module_serial_number=-1::BIGINT)
 AND (NULL::TIMESTAMP IS NULL OR erc.record_time >= NULL::TIMESTAMP)
 AND (NULL::TIMESTAMP IS NULL OR erc.record_time <= NULL::TIMESTAMP)
 AND erc.active is TRUE;

The main issue is with NESTED LOOP because it lasts more than 40 seconds. 
This is a response that I got from database:

   https://pastebin.com/VQpnTLYS
...