使用铁路3的Im和我的生产 d在Heroku。 我如何为这一问题制定适当的指数? 我不知道如何为内部人创造一种机会,使他们加入到这一时刻。
SELECT "plans".* FROM "plans"
INNER JOIN "schedules"
ON "plans".schedule_id = "schedules".id
WHERE (("schedules".user_id = 4))
你们应当能够增加一个附表索引。
add_index :schedules, :user_id
......和另一个按计划分列的指数:
add_index :plans, :schedule_id
此外,如果你重新努力装上所有附表或相关计划,你可能会使用左边:
select plans.*
from schedules
left join plans on plans.schedule_id = schedule.id
where schedules.user_id = 4
我认为,左边合在一起对你们在这里想要的东西是正确的。
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