Question

我是sql的新手，我正在尝试执行以下操作：

我的查询目前根据where子句拉回两个字段：

select distinct 
     count(distinct t1.p_id) "c1",
     count(distinct t2.sa_id) "c2" 
from capd_section t5, 
     capd_department t6,
     capd_person t1,
     capd_studentapplication t2,
     capd_module t4,
     capd_moduleapplication t3 
where (t3.ma_studentapplication(+)=t2.sa_id) and 
      (t3.ma_module=t4.m_id(+)) and 
      (t4.m_modulesection=t5.s_id(+)) and 
      (t4.m_moduledept=t6.d_id(+)) and 
      (t4.m_reference not like '%%FTA%%') and 
      **(t2.sa_reference like '212%%')** and 
      (t4.m_reference not like '%%HE%%') and 
      (t4.m_reference not like '%%PT%%') and 
      (t4.m_name not like 'NCTJ%%') and 
      (t4.m_reference not like 'ME%%') and 
      (t2.sa_student=t1.p_id) 
having (count(distinct t3.ma_id)>0)

我希望拥有相同的查询但是使用where子句（t2.sa_reference，如'213 %%'）来撤回。（当前年份和上一年度）

总共四个字段（c1，c2，c3，c4）。如果这有任何意义的话。它甚至可能吗？

非常感谢任何帮助：）

Answer 1

您只需添加或声明以检查第二个值，然后尝试查询：

select distinct 
     count(distinct t1.p_id) "c1",
     count(distinct t2.sa_id) "c2" 
from capd_section t5, 
     capd_department t6,
     capd_person t1,
     capd_studentapplication t2,
     capd_module t4,
     capd_moduleapplication t3 
where (t3.ma_studentapplication(+)=t2.sa_id) and 
      (t3.ma_module=t4.m_id(+)) and 
      (t4.m_modulesection=t5.s_id(+)) and 
      (t4.m_moduledept=t6.d_id(+)) and 
      (t4.m_reference not like '%%FTA%%') and 
      ((t2.sa_reference like '212%%')or (t2.sa_reference like '213%%')) and 
      (t4.m_reference not like '%%HE%%') and 
      (t4.m_reference not like '%%PT%%') and 
      (t4.m_name not like 'NCTJ%%') and 
      (t4.m_reference not like 'ME%%') and 
      (t2.sa_student=t1.p_id) 
having (count(distinct t3.ma_id)>0);

这里我修改了你的条件，通过使用((t2.sa_reference like '212%%')or (t2.sa_reference like '213%%'))这个子句来检查这两个值。因此，如果其中任何一个得到满足，您可以检索行。

Answer 2

只需在COUNT语句中使用CASE：

select distinct 
     count(distinct t1.p_id) "c1",
     count(distinct t2.sa_id) "c2",
     count(distinct case when t2.sa_reference like '212%%' then t1.p_id else null end) "c3",
     count(distinct case when t2.sa_reference like '212%%' then t2.sa_id else null end) "c4"

from capd_section t5, 
     capd_department t6,
     capd_person t1,
     capd_studentapplication t2,
     capd_module t4,
     capd_moduleapplication t3 
where (t3.ma_studentapplication(+)=t2.sa_id) and 
      (t3.ma_module=t4.m_id(+)) and 
      (t4.m_modulesection=t5.s_id(+)) and 
      (t4.m_moduledept=t6.d_id(+)) and 
      (t4.m_reference not like '%%FTA%%') and 
      (t4.m_reference not like '%%HE%%') and 
      (t4.m_reference not like '%%PT%%') and 
      (t4.m_name not like 'NCTJ%%') and 
      (t4.m_reference not like 'ME%%') and 
      (t2.sa_student=t1.p_id) 
having (count(distinct t3.ma_id)>0)

SQL - 相同的表where子句

2 个答案: