[英]How to do a left outer join in a eager_load in Rails?
以下查詢
Install.eager_load(customer: :invoices).includes(calendar_appointment: :technician).where("state = 'scheduled' AND start_time < ?", Date.tomorrow)
真的很慢,我希望只返回沒有關聯發票的安裝,因為這會使它運行得更快。 我該怎么做呢? 此外,任何有關提高此查詢速度的想法都會有所幫助,相應的表將被編入索引。
不知道協會是如何定義的,但這是我對它的抨擊:
Install
.joins("inner join invoices on installs.id = invoices.install_id")
.includes(calendar_appointment: :technician)
.where("state = 'scheduled' AND start_time < ? AND invoices.install_id IS NULL", Date.tomorrow)
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