SELECT f_name,l_name,teachers.first_name,teachers.t_id,p_id,paid_amount,family_id,date,sum(payments.paid_amount)
FROM payments
LEFT JOIN family ON family.id = payments.family_id
LEFT JOIN teachers ON family.teacher_id = teachers.t_id
如何完全获取所选列和sum列？ 因为sum函数使所有选定的结果成为一行
SELECT f_name,l_name,teachers.first_name,teachers.t_id,p_id,paid_amount,family_id,date
FROM payments
LEFT JOIN family ON family.id = payments.family_id
LEFT JOIN teachers ON family.teacher_id = teachers.t_id
此查询在没有总和列
的情况下正常工作答案 0 :(得分：0)
您没有告诉数据库，哪个列用于聚合数据。不知道您正在使用哪个数据库，但有些人抱怨说SQL文本中没有GROUP BY语句。
请尝试使用以下查询：
SELECT f_name,l_name,teachers.first_name,teachers.t_id,p_id,paid_amount,family_id,date,sum(payments.paid_amount)
FROM payments
LEFT JOIN family ON family.id = payments.family_id
LEFT JOIN teachers ON family.teacher_id = teachers.t_id
GROUP BY f_name,l_name,teachers.first_name,teachers.t_id,p_id,paid_amount,family_id,date
GROUP BY告诉数据库，这是聚合中的关键列。
答案 1 :(得分：0)
如果您想要所有付款，请使用子查询或class ViewModel {
func getImages() -> [UIImage] {
var images: [UIImage] = []
for i in 0..<44 {
if let image = UIImage(named: "hotDog\(i).png") {
images.append(image)
}
}
return images
}
}
class ViewController: UIViewController {
private var viewModel: ViewModel!
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
let cell = tableView.cellForRow(at: indexPath) as! CustomCell
let images = viewModel.getImages()
cell.animateImageView(withImages: images)
}
}
class CustomCell: UITableViewCell {
@IBOutlet weak var imageView: UIImageView!
func animateImageView(withImages images: [UIImage]) {
imageView.image = images.last
imageView.animationImages = images
imageView.animationDuration = TimeInterval(images.count / 20)
imageView.animationRepeatCount = 1
imageView.startAnimating()
}
}
：
join答案 2 :(得分：0)
SELECT f_name,l_name,t.first_name,t.t_id,p_id,paid_amount,family_id,date,sum(p.paid_amount)
FROM payments p,family f,teachers t where f.id = p.family_id and f.teacher_id = t.t_id
Group by f_name,l_name,teachers.first_name,teachers.t_id,p_id,paid_amount,family_id
您可以根据您的要求在Group by表达式中添加日期列。例如：
f_name,l_name,teachers.first_name,teachers.t_id,p_id,paid_amount,family_id,date