如何在 oracle 中求和 2 选择结果

Question

你好，我想把其他选择的两个结果相加

我尝试了一些方法，但我找不到任何方法请帮助我 这是我的代码

SELECT
name1,count1,count2FROM
(
    SELECT
        trade.name AS name1, COUNT(workorders.id) AS count1
    FROM      workorders
    RIGHT JOIN    trade
    ON trade.id = workorders.trade_id 
    AND     workorders.hcworkorderstat_id IN (
            SELECT     hcworkorderstat.id
            FROM       hcworkorderstat
            WHERE hcworkorderstat.code NOT IN ( 'CL','CANCEL' ))
    GROUP BY  trade.name
) tab1LEFT JOIN
(
    SELECT
        trade.name AS name2,
        COUNT(workorders.id) AS count2
    FROM
        workorders
    RIGHT JOIN
        trade
    ON
        workorders.trade_id = trade.id
    AND
        workorders.requesteddate BETWEEN '1391.01.15' AND '1396.10.15'
    GROUP BY
        trade.name
) tab2
ON tab1.name1=tab2.name2 

需要结果 count1+count2 我还需要在表中显示计数 1 和计数 2 怎么会这样？

Answer 1

“我需要计数 1 和两个的总和，我还需要在表中显示计数 1 和计数 2”

嗯，唯一的难点是 LEFT JOIN 意味着当 tab1.name1=tab2.name2 上没有匹配项时，count2 将为空。我们不能对空值进行算术运算，因此您需要将其默认为零。像这样的：

SELECT
   name1, count1, count2, count1 + nvl(count2,0) as tot FROM
(
   ...
)

Answer 2

试试这个：-

SELECT name1,count1, count2, (count_1+count_2) AS sum_of_counts
FROM
(
SELECT name1,count1, count2, case when count1>0 then count1 else 0 end as count_1, 
case when count2>0 then count2 else 0 end as count_2
FROM
 (
    SELECT
        trade.name AS name1, COUNT(workorders.id) AS count1
    FROM      workorders
    RIGHT JOIN    trade
    ON trade.id = workorders.trade_id 
    AND     workorders.hcworkorderstat_id IN (
            SELECT     hcworkorderstat.id
            FROM       hcworkorderstat
            WHERE hcworkorderstat.code NOT IN ( 'CL','CANCEL' ))
    GROUP BY  trade.name
 ) tab1
LEFT JOIN
 (
    SELECT
        trade.name AS name2,
        COUNT(workorders.id) AS count2
    FROM
        workorders
    RIGHT JOIN
        trade
    ON
        workorders.trade_id = trade.id
    AND
        workorders.requesteddate BETWEEN '1391.01.15' AND '1396.10.15'
    GROUP BY
        trade.name
 ) tab2
ON tab1.name1=tab2.name2
) a;