MySQL想要将两列和为UNION

Question

我有两张MySQL表。每个表都有以下字段：

• p_id
• hours_value
• minute_value

我想将这两个表的小时和分钟字段之和为p_id或project_id。下面的查询没有提供预期的结果。

SELECT SUM(hours_value), SUM(minute_value)
    FROM timesheet_master 

    UNION 
    SELECT `hours_value` 
    FROM timesheet_master_archive
    WHERE `p_id` = '1'

Answer 1

我想你想把这些行相加，然后计算和？这将是：

select sum(hours_value), sum(minute_value)
from 
(
  select hours_value, minute_value from t1 where p_id = 1
  union all
  select hours_value, minute_value from t2 where p_id = 1
) both_tables;

Answer 2

您可以在下面尝试-对于联合，在两个选择查询中，您的no列都应该相等。

SELECT SUM(hours_value) as hrval, SUM(minute_value) as minval
FROM timesheet_master 
UNION 
SELECT `hours_value`,minute_value
ROM timesheet_master_archive WHERE `p_id` = '1'

Answer 3

我发现的查询：

SELECT SUM(hours_value) as hrval, SUM(minute_value) as minval
FROM timesheet_master WHERE `p` = '1'
UNION 
SELECT `hours_value`,minute_value
FROM timesheet_master_archive WHERE `p_id` = '1'