求助一个问题，关于协程和gorm的

求助一个问题，关于协程和gorm的

1 year ago

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一切都源于我开发中发现的一个bug，简单描述就是先insert 了一条数据，然后开启了一个协程，直接进行查询刚才插入的数据，竟然没查到。

func Test(t *testing.T) {

    record := &model.ContentCoursePracticeRecord{
        Cid:      0,
        Uid:      1,
        Complete: 1,
        Type:     2,
        Duration: 100,
        Ctime:    time.Now(),
        Uptime:   time.Now(),
    }
    err := dao.ContentCoursePracticeRecordDao.Create(record)
    assert.Equal(t, err, nil)
    go func() {
        // 查询0元购活动
        var (
            duration int
        )

        db, err := utils.GetDB()

        if err != nil {
            assert.Equal(t, err, nil)
        }

        if ret := db.Model(&model.ContentCoursePracticeRecord{}).
            Where("isdel = 0 and uid = ?", 1).
            Where("ctime >= ?", time.Now().Format("2006-01-02")).
            Select("sum(duration) as duration").
            Find(&duration); ret.Error != nil {
            // 此处报错 ，说明没有数据
            //sql: Scan error on column index 0, name "duration": converting NULL to int is unsupported
            assert.Equal(t, err, nil)
        }
    }()
}

他不是一个必现的问题，我也没有成功复现出来后来把查询从写成挪出去就没有问题了，但是也没有想明白问题？望各位大佬指点！

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