mysql：Incorrect datetime value: ‘‘

最近在做调度时，需要生成中间表数据，使用sql如下：

-- 脚本1
INSERT INTO ct_zr_pay_paid_overdue_payment_record ( created_time)
SELECT  now()
FROM (business_contract bc, fund_channel fc, acct_loan al, acct_payment_schedule aps)
	LEFT JOIN plan_payment_way ppw ON aps.serialno = ppw.serialno
WHERE bc.fundno = fc.fundno
	AND bc.serialno = al.serialno
	AND bc.serialno = aps.objectno
	AND bc.orgId = 'EDU2017071000000002'
	AND date_format('20200211', '%Y%m') = date_format(aps.finishdate, '%Y%m')
	AND aps.finishdate < date_format('20200211', '%Y/%m/%d')
-- 脚本2
INSERT INTO ct_zr_pay_paid_overdue_payment_record ( created_time)
SELECT  now()
FROM (business_contract bc, fund_channel fc, acct_loan al, acct_payment_schedule aps)
	LEFT JOIN plan_payment_way ppw ON aps.serialno = ppw.serialno
WHERE bc.fundno = fc.fundno
	AND bc.serialno = al.serialno
	AND bc.serialno = aps.objectno
	AND bc.orgId = ''
	AND date_format('20200211', '%Y%m') = date_format(aps.finishdate, '%Y%m')
	AND aps.finishdate < date_format('20200211', '%Y/%m/%d')

 在执行时两个脚本查询出的数据都是0条，但是脚本1报错，脚本2不报错，脚本1报错：Incorrect datetime value: ''，经过排查，可以通过两个方法避免报错问题，但生产上还是需要用方法二

-- 方法一
-- 允许无效格式日期时间
-- 详细说明见stackOverFlow:
--https://stackoverflow.com/questions/22806870/incorrect-datetime-value-database-error-number-1292
	SET SESSION SQL_MODE='ALLOW_INVALID_DATES'
 
-- 方法二
-- 在查询后在union all一个空值即可
  INSERT INTO ct_zr_pay_paid_overdue_payment_record ( created_time)
SELECT  now()
FROM (business_contract bc, fund_channel fc, acct_loan al, acct_payment_schedule aps)
	LEFT JOIN plan_payment_way ppw ON aps.serialno = ppw.serialno
WHERE bc.fundno = fc.fundno
	AND bc.serialno = al.serialno
	AND bc.serialno = aps.objectno
	AND bc.orgId = 'EDU2017071000000002'
	AND date_format('20200211', '%Y%m') = date_format(aps.finishdate, '%Y%m')
	AND aps.finishdate < date_format('20200211', '%Y/%m/%d')
	
	union all 
	select now() from ct_zr_pay_paid_overdue_payment_record where 1=2