同时计算多个项

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我有以下结构和查询代码：

type result struct {
    startedlast15minutes  int `gorm:"column:started_last_15_minutes"`
    startedlast60minutes  int `gorm:"column:started_last_60_minutes"`
    startedlast24hours    int `gorm:"column:started_last_24_hours"`
    startedlast48hours    int `gorm:"column:started_last_48_hours"`
    finishedlast15minutes int `gorm:"column:finished_last_15_minutes"`
    finishedlast60minutes int `gorm:"column:finished_last_60_minutes"`
    finishedlast24hours   int `gorm:"column:finished_last_24_hours"`
    finishedlast48hours   int `gorm:"column:finished_last_48_hours"`
}
statsresult := result{}
    err = g.db.
        raw(`
    select 
        count(*) filter (where oe.timestamp  >= current_timestamp - interval '15 minutes' and type = 1 ) as started_last_15_minutes,
        count(*) filter (where oe.timestamp  >= current_timestamp - interval '1 hour' and type = 1 ) as started_last_60_minutes,
        count(*) filter (where oe.timestamp  >= current_timestamp - interval '24 hours' and type = 1 ) as started_last_24_hours,
        count(*) filter (where oe.timestamp  >= current_timestamp - interval '48 hours' and type = 1 ) as started_last_48_hours,
        count(*) filter (where oe.timestamp  >= current_timestamp - interval '15 minutes' and type = 37 ) as finished_last_15_minutes,
        count(*) filter (where oe.timestamp  >= current_timestamp - interval '1 hour' and type = 37 ) as finished_last_60_minutes,
        count(*) filter (where oe.timestamp  >= current_timestamp - interval '24 hours' and type = 37 ) as finished_last_24_hours,
        count(*) filter (where oe.timestamp  >= current_timestamp - interval '48 hours' and type = 37 ) as finished_last_48_hours
    from onboarding_events as oe
    `).
        scan(&statsresult).
        error

但是如果我想将其翻译成 gorm 语法，我只能通过多个查询找到这样的解决方案：

    g.db.
        Model(model.OnboardingEvent{}).
        Where("timestamp  >= current_timestamp - interval '24 hours' and type = 37").
        Count(&singleCound).
        Where("timestamp  >= current_timestamp - interval '48 hours' and type = 37").
        Count(&singleCount2)

gorm 是否在一个查询中提供多个计数？

正确答案

这是查询构建器的一个常见问题，这些函数不是很复杂，因此会被覆盖，而不是附加的（如您所希望的情况）。正如您在 source code 中看到的，如果它已经找到一个计数，则不会添加新计数。

您可以通过添加自己的接口函数来研究 GORM 文档。也许像 AddCount() 这样的东西，然后从源代码中借用代码并使其实际上添加更多计数，而不是忽略多个计数。

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