获取记录但不通过与工会合作来订购

Question

我有两个表，并且正在使用UNION从两个表中获取记录。 我正在获取记录，但记录未按DESC顺序显示。 我的意思是按命令不起作用。

(
  select l.c_id,l.companyname, l.c_firstname, l.c_lastname, emp.firstname as empfirstname,emp.lastname as emplastname
  from tbl_lead as l
  inner join tbl_employee as emp on l.createby=emp.id
  WHERE l.leadstatus IN (2,3)
  ORDER BY l.date_of_created DESC
) UNION ALL (
  select l.c_id,l.companyname, l.c_firstname, l.c_lastname, emp.firstname as empfirstname,emp.lastname as emplastname
  from tbl_leadUpload as l
  inner join tbl_employee as emp on l.createby=emp.id
  where l.leadstatus IN (2,3)
  ORDER BY l.date_of_created DESC
)

您能帮我解决这个问题吗？

Answer 1

将ORDER BY子句带到两个子查询共同使用的主子查询：

select c_id, companyname, c_firstname, c_lastname, empfirstname, emplastname
  from
  (
   select l.date_of_created,l.c_id,l.companyname, l.c_firstname, l.c_lastname,   
          emp.firstname as empfirstname,emp.lastname as emplastname 
     from tbl_lead as l inner join tbl_employee as emp on l.createby=emp.id 
    where l.leadstatus in (2,3)  
    union all 
   select l.date_of_created,l.c_id,l.companyname, l.c_firstname, l.c_lastname,                        
          emp.firstname as empfirstname,emp.lastname as emplastname 
     from tbl_leadUpload as l inner join tbl_employee as emp on l.createby=emp.id        
    where l.leadstatus in (2,3) 
  ) q
order by date_of_created desc

Answer 2

对每个子查询进行排序，然后应用UNION ALL并不意味着将对结果进行排序。
您可以做的是也选择您要排序的列，并对结果进行排序：

select 
  l.date_of_created, l.c_id, l.companyname, l.c_firstname, l.c_lastname, 
  emp.firstname as empfirstname, emp.lastname as emplastname 
from tbl_lead as l inner join tbl_employee as emp 
on l.createby=emp.id 
WHERE l.leadstatus IN (2,3) 
UNION ALL 
select 
  l.date_of_created, l.c_id, l.companyname, l.c_firstname, l.c_lastname, 
  emp.firstname as empfirstname, emp.lastname as emplastname 
from tbl_leadUpload as l inner join tbl_employee as emp 
on l.createby=emp.id 
where l.leadstatus IN (2,3) 
ORDER BY date_of_created DESC

或者，如果您不想选择date_of_created ：

select 
  t.c_id, companyname, t.c_firstname, t.c_lastname, t.empfirstname, t.emplastname
from (
  select 
    l.date_of_created, l.c_id, l.companyname, l.c_firstname, l.c_lastname, 
    emp.firstname as empfirstname, emp.lastname as emplastname 
  from tbl_lead as l inner join tbl_employee as emp 
  on l.createby=emp.id 
  WHERE l.leadstatus IN (2,3) 
  UNION ALL 
  select 
    l.date_of_created, l.c_id, l.companyname, l.c_firstname, l.c_lastname, 
    emp.firstname as empfirstname, emp.lastname as emplastname 
  from tbl_leadUpload as l inner join tbl_employee as emp 
  on l.createby=emp.id 
  where l.leadstatus IN (2,3) 
) as t
ORDER BY t.date_of_created DESC

Answer 3

select l.c_id, l.companyname, l.c_firstname, l.c_lastname, 
       e.firstname as empfirstname, e.lastname as emplastname 
from ((select l.created_by, l.date_of_created, l.c_id, l.companyname, l.c_firstname, l.c_lastname
       from tbl_lead l
       where l.leadstatus in (2, 3)
      ) union all
      (select l.created_by, l.date_of_created, l.c_id, l.companyname, l.c_firstname, l.c_lastname
       from tbl_leadupdate l
       where l.leadstatus in (2, 3)
      )
     ) l join
     tbl_employee as emp 
     on l.createby = emp.id 
order by l.date_of_created desc;

如果两个“线索”表具有相同的列，则需要更少的输入：

select l.c_id, l.companyname, l.c_firstname, l.c_lastname, 
       e.firstname as empfirstname, e.lastname as emplastname 
from ((select l.*
       from tbl_lead l
       where l.leadstatus in (2, 3)
      ) union all
      (select l.*
       from tbl_leadupdate l
       where l.leadstatus in (2, 3)
      )
     ) l join
     tbl_employee as emp 
     on l.createby = emp.id 
order by l.date_of_created desc;