在sql中合并几乎重复的记录

Question

大家好……

我有两个表，它们的结构是相同的......

表日志详情

Date              Time         CardID        Status  
2012-01-20        00:00:00     A1            ABSENT
2012-01-20        00:00:00     B1            ABSENT
2012-01-20        00:00:00     C3            ABSENT
2012-01-20        00:00:00     D1            ABSENT

表preStatus

Date            Time        CardID        Status
2012-01-20     07:00:10     A1            COMING
2012-01-20     07:10:00     C3            COMING
2012-01-20     08:00:00     B1            LATE
2012-01-20     17:00:00     B1            BACK
2012-01-20     17:10:10     A1            BACK
2012-01-20     17:13:00     C3            BACK

合并后

Date
2012-01-20     07:00:10     A1            COMING
2012-01-20     07:10:00     C3            COMING
2012-01-20     08:00:00     B1            LATE
2012-01-20     00:00:00     D1            ABSENT
2012-01-20     17:00:00     B1            BACK
2012-01-20     17:10:10     A1            BACK
2012-01-20     17:13:00     C3            BACK

我如何合并这两个表，因为在表 b 中有重复的记录，当我这样做时 合并...

merge into logDetail as Target 
using preStatus as Source
on Target.L_Date=Source.L_Date
and Target.L_Time='00:00:00'
and Target.L_CardID=Source.L_CardID 
when matched then

update set Target.L_Status=Source.L_Status,
Target.L_Time=Source.L_Time
when not matched then
insert (L_Date,L_Time,L_CardID,L_Status) 
                           values(Source.L_Date,Source.L_Time,Source.L_CardID,Source.L_Status);

它说 MERGE 语句多次尝试更新或删除同一行

非常感谢任何帮助。

Answer 1

您似乎不想合并表，因为 CardID 不是主键。

您似乎希望保留 Status = "COMING" 的条目，即使有新条目 stats = "BACK"。

我建议您分两步执行此操作，首先插入 preStatus 数据，然后删除存在“COMING”和“BACK”行的“ABSENT”行。

/* Insert new data */
insert logDetail
select * from preStatus

/* Delete Absent rows where there is a COMING or BACK row for the same item on the same day */
Delete logDetail
from logDetail ld1
where 
    /* Absent rows only */
    ld1.time = '00:00:00'
and ld1.Status = 'ABSENT'
/*  And there must be a COMING or BACK row for the same card on the same day */
and exists (
   select 1 from logDetail ld2
   where ld2.Date = ld1.Date
   and ld2.CardID = ld1.CardID
   and ld2.Time > '00:00:00'
   and ld2.Status <> 'ABSENT'
)

要删除具有相同日期、卡 ID 和相同状态但有更晚时间的行：

Delete logDetail
from logDetail ld1
where 
ld1.status in ('COMING', 'BACK')
/*  COMING or BACK row only */ 
      /* for the same card on the same day, with a later time*/
and exists (
   select 1 from logDetail ld2
   where ld2.Date = ld1.Date      
   and ld2.CardID = ld1.CardID
   and ld2.Status = ld1.Status
   and ld2.Time > ld1.Time
)

Answer 2

匹配时不做任何事情，这应该解决吗？