Вчерашний запрос, "заморозивший" миграцию на три часа:
SELECT entity_id, MAX(start_date), MAX(end_date) FROM ( SELECT entity_id, MAX(start_date) start_date, NULL AS end_date FROM audit_log WHERE attr = 'reviewed' AND newValue = 'true' GROUP BY entity_id UNION ALL SELECT entity_id, NULL AS start_date, MAX(end_date) end_date FROM audit_log WHERE attr = 'overriden' AND newValue = 'true' GROUP BY entity_id ) a GROUP BY entity_id;
можно было бы написать сильно оптимальнее вот так:
SELECT entity_id, MAX(if(attr = 'reviewed', NULL, start_date)) AS start_date, MAX(if(attr = 'reviewed', end_date, NULL)) end_date FROM audit_log WHERE (attr = 'reviewed' OR attr='overriden') AND newValue = 'true' GROUP BY entity_id;
При сильно похожих WHERE в таких конструкциях, удобнее схлопнуть UNION и "на лету" подставлять в SELECT нужное значение через if.
Вчерашний запрос, "заморозивший" миграцию на три часа:
SELECT entity_id, MAX(start_date), MAX(end_date) FROM ( SELECT entity_id, MAX(start_date) start_date, NULL AS end_date FROM audit_log WHERE attr = 'reviewed' AND newValue = 'true' GROUP BY entity_id UNION ALL SELECT entity_id, NULL AS start_date, MAX(end_date) end_date FROM audit_log WHERE attr = 'overriden' AND newValue = 'true' GROUP BY entity_id ) a GROUP BY entity_id;
можно было бы написать сильно оптимальнее вот так:
SELECT entity_id, MAX(if(attr = 'reviewed', NULL, start_date)) AS start_date, MAX(if(attr = 'reviewed', end_date, NULL)) end_date FROM audit_log WHERE (attr = 'reviewed' OR attr='overriden') AND newValue = 'true' GROUP BY entity_id;
При сильно похожих WHERE в таких конструкциях, удобнее схлопнуть UNION и "на лету" подставлять в SELECT нужное значение через if.
BY Developer's mind
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Telegram has exploded as a hub for cybercriminals looking to buy, sell and share stolen data and hacking tools, new research shows, as the messaging app emerges as an alternative to the dark web.An investigation by cyber intelligence group Cyberint, together with the Financial Times, found a ballooning network of hackers sharing data leaks on the popular messaging platform, sometimes in channels with tens of thousands of subscribers, lured by its ease of use and light-touch moderation.
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