我如何为这个SQL (Oracle)写一个更新查询我刚刚写在下面,我想使用多个表(其中3个)执行如下更新操作:
update payroll.emp_appointments
set e.sales=w.sales
where the details below
select w.storecode,w.salespersoncode,w.sumsales,w.truncateddate, c.customerid,
e.firstname,e.lastname,c.contactid
from weekstat w, sysdba.contact_retail c, payroll.emp_appointments e where
c.customerid=w.customerid
and cast(w.salespersoncode as char(6))=e.emp_num
and trunc(e.tradingdate)=w.truncateddate
and e.contactid=c.contactid
and e.storecode=cast(e.storecode as varchar2(6))
and e.sales=0.00
and e.tradingdate > sysdate-10
我尝试在创建临时表后执行以下操作,但它似乎更新了emp_appointments表中的所有行,这是我不想做的:
update payroll.emp_appointments e
set e.sales= (
select ue.sumsales
from update_emp_sales_temp ue
where e.contactid=ue.contactid and
e.emp_num=ue.salespersoncode and
e.storecode=ue.storecode and
e.firstname=ue.firstname and
e.lastname=ue.lastname and
trunc(e.tradingdate)=ue.truncateddate)
where e.tradingdate>sysdate-30;
更容易记住结构
update <select with all the joins> set <set conditions>
在你的例子中:
UPDATE
(select w.sales src, e.sales dst
from weekstat w, sysdba.contact_retail c, payroll.emp_appointments e where
c.customerid=w.customerid
and cast(w.salespersoncode as char(6))=e.emp_num
and trunc(e.tradingdate)=w.truncateddate
and e.contactid=c.contactid
and e.storecode=cast(e.storecode as varchar2(6))
and e.sales=0.00
and e.tradingdate > sysdate-10)
SET dst = src
只需记住您只需要更新一个表
另一种使用MERGE:
的方法MERGE INTO payroll.emp_appointments e
USING (select w.sales, e.emp_num
from weekstat w, sysdba.contact_retail c, payroll.emp_appointments e where
c.customerid=w.customerid
and cast(w.salespersoncode as char(6))=e.emp_num
and trunc(e.tradingdate)=w.truncateddate
and e.contactid=c.contactid
and e.storecode=cast(e.storecode as varchar2(6))
and e.sales=0.00
and e.tradingdate > sysdate-10) subquery
ON (e.emp_num = subquery.emp_num)
WHEN MATCHED THEN UPDATE SET e.sales = subquery.sales;
我没有足够的信息来详细说明你的逻辑来修复上面的查询,所以这里是第三个选项:)(它也可能失败,更多关于它在底部):
UPDATE payroll.emp_appointments e
SET
sales = (select w.sales from weekstat w, sysdba.contact_retail c
where
c.customerid=w.customerid
and cast(w.salespersoncode as char(6))=e.emp_num
and trunc(e.tradingdate)=w.truncateddate
and e.contactid=c.contactid)
)
WHERE e.sales=0.00
and and e.tradingdate > sysdate-10
and (e.emp_num, trunc(e.tradingdate), e.contactid)
in
(select w.salespersoncode, w.truncateddate, c.contactid from
weekstat w, sysdba.contact_retail c
where c.customerid=w.customerid)
我不喜欢它,因为你基本上重复了两次逻辑。你可能会在select 'sales = '之后得到一个错误,它没有返回比例值,但我没有足够的信息来解决这个问题。因此,您有责任确保select对于将要更新的表e
中的任何行都返回1行。另外,我删除了看起来多余的条件and e.storecode=cast(e.storecode as varchar2(6))
。
谢谢Vav,我尝试了以下方法,现在它工作了:
UPDATE payroll.emp_appointments e
SET (e.sales) = (
SELECT w.sumsales
FROM weekstat w, sysdba.contact_retail c
where
c.customerid=w.customerid
and cast(w.salespersoncode as char(6))=e.emp_num
and trunc(e.tradingdate)=w.truncateddate
and e.contactid=c.contactid
and e.storecode=cast(e.storecode as varchar2(6))
and e.sales=0.00
and e.tradingdate > sysdate-10)
where exists (SELECT w.sumsales
FROM weekstat w, sysdba.contact_retail c
where
c.customerid=w.customerid
and cast(w.salespersoncode as char(6))=e.emp_num
and trunc(e.tradingdate)=w.truncateddate
and e.contactid=c.contactid
and e.storecode=cast(e.storecode as varchar2(6))
and e.sales=0.00
and e.tradingdate > sysdate-10)