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在具有小 LIMIT 的外部查询中添加 ORDER BY 时,复杂视图会变慢

我在视图中有一个非常大的查询(让我们称之为a_sql),这真的很快,除非我ORDER BYSELECT带有小的外部使用LIMIT

SELECT
customs.id AS custom_id, customs.custom_name AS custom_name, customs.slug AS slug, customs.use_case AS custom_use_case,
SUM(CASE WHEN designers.id = orders.user_id AND orders.bulk = 't' THEN order_rows.quantity ELSE 0 END) AS sale_bulk,
SUM(CASE WHEN designers.id = orders.user_id AND orders.bulk = 'f' THEN order_rows.quantity ELSE 0 END) AS sale_not_bulk,
SUM(CASE WHEN designers.id = orders.user_id THEN order_rows.quantity ELSE 0 END) AS sale_total,
SUM(CASE WHEN designers.id <> orders.user_id AND orders.bulk = 't' THEN order_rows.quantity ELSE 0 …
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postgresql performance optimization view postgresql-9.4 postgresql-performance

2
推荐指数
2
解决办法
1457
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