it也有一段時間了,剛開始的時候``````
的困難主要是在程式語言上,陣列,邏輯,演算法,...
這些都過來了之後,困難就上公升到資料庫設計上了.
以及資料邏輯.
乙個優秀的系統,會整合優秀的程式和優秀的資料庫設計.
要做到這點得有足夠的經驗.
這是我寫的乙個結合uinon的巢狀查詢.
將五個方面的報表放到乙個臨時表裡,再從臨時表裡,將所要的資料查詢出來.
$sql="select type , sum( yjsl ) as yjsl , sum( yysl ) as yysl, sum( jyrs ) as jyrs, sum( jycs ) as jycs
from (
select c.mc as
type , count( d.lsh ) as yjsl, 0 as yysl, 0 as jyrs, 0 as jycs
from sys_dzxxb as b, sys_jcb as c, sys_dzyjb as d
where b.bm = c.lsh
and d.dzlsh = b.lsh
group by c.mc
union select c.mc as
type , 0 as yjsl, count( e.lsh ) as yysl, 0 as jyrs, 0 as jycs
from sys_dzxxb as b, sys_jcb as c, sys_dzyy as e
where b.bm = c.lsh
and e.dzlsh = b.lsh
group by c.mc
union select c.mc as
type , 0 as yjsl, 0 as yysl, count( distinct e.dzlsh ) as jyrs, 0 as jycs
from sys_dzxxb as b, sys_jcb as c, sys_ltxxb as e
where b.bm = c.lsh
and e.dzlsh = b.lsh
group by c.mc
union select c.mc as
type , 0 as yjsl, 0 as yysl, 0 as jyrs, count( distinct e.lsh ) as jycs
from sys_dzxxb as b, sys_jcb as c, sys_ltxxb as e
where b.bm = c.lsh
and e.dzlsh = b.lsh
group by c.mc
) as temptable
group by type ";
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