Question

我需要帮助更新日历表。我有2个表，一个事务表（表T）和一个日历表（表C）。我试图在日期可用时用应用程序ID（app_id）和emp_Id更新日历表，如果日期重叠则不应更新。例如

表T

app_id  emp_id stdate      eddate      priority 
-----------------------------------------------     
1       15     2015-01-03  2015-01-05   1
2       18     2015-01-04  2015-01-06   2

表C

dates        app_id    empid
----------------------------
2015-01-03     null    null
2015-01-04     null    null
2015-01-05     null    null

运行更新后，结果应为

表C

dates        app_id    empid
----------------------------
2015-01-03     1        15
2015-01-04     1        15
2015-01-05     1        15

Answer 1

我倾向于使用apply执行此操作：

update c
    set app_id = t.app_id,
        empid = t.empid
    from table_c c apply
         (select top 1 t.*
          from table_t t
          where tc.dates >= t.stdate and
                tc.dates <= t.eddate
          order by t.priority
         ) t;

Answer 2

我把它写在了我的头顶，我希望它适合你：

UPDATE TC
SET app_id = (SELECT TOP 1 app_id FROM TABLE_T TT WHERE TC.dates BETWEEN TT.stdate AND tt.eddate ORDER BY TT.priority ASC),
empid = (SELECT TOP 1 emp_id FROM TABLE_T TT WHERE TC.dates BETWEEN TT.stdate AND tt.eddate ORDER BY TT.priority ASC)
FROM TABLE_C TC

您可以先使用此查询进行调试：

SELECT TC.*,
new_app_id = (SELECT TOP 1 app_id FROM TABLE_T TT WHERE TC.dates BETWEEN TT.stdate AND tt.eddate ORDER BY TT.priority ASC),
new_empid = (SELECT TOP 1 emp_id FROM TABLE_T TT WHERE TC.dates BETWEEN TT.stdate AND tt.eddate ORDER BY TT.priority ASC)
FROM TABLE_C TC

我在您的示例中使用了emp_id和empid。

SQL Server重叠日期

2 个答案: