Question

这是我的代码：

    charge_count = func.count(ChargeLog).label('charge_count')
    q = (session.query(PaymentProfile, charge_count)
         .outerjoin(ChargeLog, ChargeLog.profile_id == PaymentProfile._id)
         .filter(PaymentProfile.date_expiry_utc >= datetime.datetime.utcnow() - datetime.timedelta(days=(TOTAL_TIMES_TO_CHARGE - charging_attempt_0idx)))
         .filter(PaymentProfile.status == payments.ProfileStatus.ACTIVE)
         .filter(ChargeLog.date_created_utc > PaymentProfile.date_charged_utc)
         .group_by(PaymentProfile)
         .having(charge_count == charging_attempt_0idx))

但是，我收到sqlalchemy.exc.ProgrammingError: (psycopg2.ProgrammingError) can't adapt type 'DeclarativeMeta'的错误。

具体来说：

sqlalchemy.exc.ProgrammingError：（psycopg2.ProgrammingError）无法调整类型＆＃39; DeclarativeMeta＆＃39; [SQL：＆＃39; SELECT payment_profile._id AS payment_profile__id，payment_profile.sb_org_id AS payment_profile_sb_org_id，payment_profile.plan_id AS payment_profile_plan_id，payment_profile.status AS payment_profile_status，payment_profile.date_created_utc AS payment_profile_date_created_utc，payment_profile.date_updated_utc AS payment_profile_date_updated_utc，payment_profile.date_charged_utc AS payment_profile_date_charged_utc， payment_profile.date_expiry_utc AS payment_profile_date_expiry_utc，payment_profile.payment_method_id AS payment_profile_payment_method_id，count（％（param_1）s）AS charge_count \ nFROM payment_profile LEFT OUTER JOIN charge_log ON charge_log.profile_id = payment_profile._id \ nWHERE payment_profile.date_expiry_utc＆gt; =％（date_expiry_utc_1）s AND payment_profile.status =％（status_1）s AND charge_log.date_created_utc＆gt; payment_profile.date_charged_utc GROUP BY payment_profile._id，payment_profile.sb_org_id，payment_profile.plan_id，payment_profile.status，payment_profile.date_created_utc，payment_profile.date_updated_utc，payment_profile.date_charged_utc，payment_profile.date_expiry_utc，payment_profile.payment_method_id \ nHAVING count（％（param_1）s） =％（param_2）s＆＃39;] [参数：{＆＃39; date_expiry_utc_1＆＃39 ;: datetime.datetime（2017,2,14,9,2,11,353027），＆＃39; param_1＆＃39; ：，＆＃39; status_1＆＃39;：＆＃39;有效＆＃39;，＆＃39; param_2＆＃39;：0}]

我将其归因于'param_1': <class 'sb_base.model.ChargeLog'>，charge_count未将having转换为要在var pixelWidth = Convert.ToInt32(userControl.RenderSize.Width); var pixelHeight = Convert.ToInt32(userControl.RenderSize.Height); RenderTargetBitmap renderTargetBitmap = new RenderTargetBitmap(pixelWidth, pixelHeight, 96, 96, PixelFormats.Default); renderTargetBitmap.Render(userControl); PngBitmapEncoder pngImage = new PngBitmapEncoder(); pngImage.Frames.Add(BitmapFrame.Create(renderTargetBitmap)); SaveFileDialog dlg = new SaveFileDialog { DefaultExt = "png", Filter = "Png Files|*.png" }; if (dlg.ShowDialog() == true) { using (Stream fileStream = File.Create(dlg.FileName)) { pngImage.Save(fileStream); } }条件中解析的标签。

我该如何解决这个问题？

Answer 1

您需要使用ChargeLog表中的列，而不是表映射对象本身。使用主键：

# assumption: ChargeLog.id is the primary key
charge_count = func.count(ChargeLog.id).label('charge_count')

这会在SELECT列和HAVING子句中插入相同的表达式;您通常无法在HAVING中使用标签：

SELECT
  -- more columns
  count(charge_log.id) AS charge_count
-- FROM, OUTER JOIN, WHERE, GROUP_BY
HAVING count(charge_log.id)

如何在func.count上执行HAVING？

1 个答案: