Oracle中單個查詢中的多次計數

Question

是否有一種簡單的方法可以實現此查詢結果以提高其性能。我不想爲每個選擇加入兩張表格。

select Product, LCTL, LQ, LCTQL from 
(
(select 'Phone/HSI' as Product, (select count(1) as "LCTL" from tasks t,task_categories c where t.category_id=c.category_id and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))>=?1 and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))<=?2 and c.category_long_name='m ECOMM ORD') as LCTL, 
(select count(1) as "LCTL" from tasks t,task_categories c where t.category_id=c.category_id and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))>=?1 and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))<=?2 and (c.category_long_name='CRIS ECOMM ORD' or c.category_long_name='CRIS ECOMM HELD')) as LQ, 
(select count(1) as "LCTL" from tasks t,task_categories c where t.category_id=c.category_id and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))>=?1 and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))<=?2 and (c.category_long_name='CRIS ECOMM ORD' or c.category_long_name='CRIS ECOMM HELD' or c.category_long_name='m ECOMM ORD')) as LCTQL from dual 
union all 

select '(Phone/HSI) + Prism' as Product,(select count(1) as "LCTL" from tasks t,task_categories c where t.category_id=c.category_id and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))>=?1 and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))<=?2 and c.category_long_name='m ECOMM PRISM') as LCTL, 
(select count(1) as "LCTL" from tasks t,task_categories c where t.category_id=c.category_id and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))>=?1 and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))<=?2 and c.category_long_name='CRIS ECOMM PRISM') as LQ, 
(select count(1) as "LCTL" from tasks t,task_categories c where t.category_id=c.category_id and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))>=?1 and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))<=?2 and (c.category_long_name='m ECOMM PRISM' or c.category_long_name='CRIS ECOMM PRISM')) as LCTQL from dual 

union all 
select '(Phone/HSI) + DTV' as Product,(select count(1) as "LCTL" from tasks t,task_categories c where t.category_id=c.category_id and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))>=?1 and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))<=?2 and c.category_long_name='m ECOMM DTV') as LCTL, 
(select count(1) as "LCTL" from tasks t,task_categories c where t.category_id=c.category_id and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))>=?1 and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))<=?2 and c.category_long_name='CRIS ECOMM DTV') as LQ, 
(select count(1) as "LCTL" from tasks t,task_categories c where t.category_id=c.category_id and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))>=?1 and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))<=?2 and (c.category_long_name='m ECOMM DTV' or c.category_long_name='CRIS ECOMM DTV')) as LCTQL from dual 

union all 
select 'Total' as Product,(select count(1) as "LCTL" from tasks t,task_categories c where t.category_id=c.category_id and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))>=?1 and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))<=?2 and (c.category_long_name='m ECOMM DTV' or c.category_long_name='m ECOMM PRISM' or c.category_long_name='m ECOMM DTV')) as LCTL, 
(select count(1) as "LCTL" from tasks t,task_categories c where t.category_id=c.category_id and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))>=?1 and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))<=?2 and (c.category_long_name='CRIS ECOMM DTV' or c.category_long_name='CRIS ECOMM PRISM' or c.category_long_name='CRIS ECOMM ORD' or c.category_long_name='CRIS ECOMM HELD')) as LQ, 
(select count(1) as "LCTL" from tasks t,task_categories c where t.category_id=c.category_id and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))>=?1 and to_date(to_char(t.user_create_date,'DD-MON-YYYY'))<=?2 and (c.category_long_name='m ECOMM DTV' or c.category_long_name='m ECOMM PRISM' or c.category_long_name='m ECOMM DTV' or c.category_long_name='CRIS ECOMM DTV' or c.category_long_name='CRIS ECOMM PRISM' or c.category_long_name='CRIS ECOMM ORD' or c.category_long_name='CRIS ECOMM HELD')) as LCTQL from dual) 
) 

輸出應該如下：

Product     LCTL LQ  LCTQL 
Phone/HSI   17209 39849 57058 
(Phone/HSI) + Prism 4095 6 4101 
(Phone/HSI) + DTV 6192 1 6193 


Total 10287 39856 50143 

Answer 1

我覺得你的查詢可以這樣寫：

SELECT 
    product, 
    SUM(CASE WHEN c.category_long_name = 'm ECOMM ORD'  THEN 1 ELSE 0 END) AS LCTL, 
    SUM(CASE WHEN c.category_long_name = 'CRIS ECOMM ORD' 
      OR c.category_long_name = 'CRIS ECOMM HELD' THEN 1 ELSE 0 END) AS LQ, 
    SUM(CASE WHEN c.category_long_name IN('CRIS ECOMM ORD', 
             'CRIS ECOMM HELD', 
             'm ECOMM ORD')  THEN 1 ELSE 0 END) AS LCTQ, 
    SUM(CASE WHEN c.category_long_name = 'm ECOMM PRISM'  THEN 1 ELSE 0 END) AS lccc, 
    ... 
    ... 
    COUNT(*) AS "Total" 
FROM tasks t 
INNER JOIN task_categories c ON t.category_id=c.category_id 
WHERE to_date(to_char(t.user_create_date, 'DD-MON-YYYY')) >= ?1 
    and to_date(to_char(t.user_create_date, 'DD-MON-YYYY')) <= ?2 
GROUP BY product; 

使用CASE表達，與GROUP BY product，你可以做到這一點一個查詢。這是基本的想法。

另外，您可能需要在Oracle中使用pivot運算符，但不清楚是否可以使用pivot運算符來編寫運算符。