Question

在SQL Server中，我具有以下表结构

alert_details_status 表：

alertTypeId macId     timeStamp     is_notified  escalation_status  alertType
123         13446   1547722123000       true       completed          408

alert_details 表：

basicid alertType   alertTypeId alertDescription    macId     timeStamp   companyId     alertName            alertCondition  unitType   channelType  alertValue expectedValue
1234     406            123         testalert       13446   1547722123000   1234     test alert name            testalert   Centimeters   length        50          60
1295     409            127         testalert       13448   1547722123000   1234     test alert name            testalert   Centimeters   length        50.2        60.3
1298     409            128         testalert       13448   1547722123000   1234     test alert name            testalert   Centimeters   length        50.2        60.3
1238     408            123         testalert       13446   1547722123000   1234     test alert name            testalert   Centimeters   length        50.2        60.3
1255     409            128         testalert       13448   1548135899000   1234     test alert name            testalert   Centimeters   length        50.2        60.3
1256     409            128         testalert       13448   1548135899000   1234     test alert name            testalert   Centimeters   length        50.2        60.3
1251     408            123         testalert       13446   1548148705000   1234     test alert name            testalert   Centimeters   length        50.2        60.3

如果alert_details_status表记录的每个timestamp >30 minutes(compared to present time)，alertTypeId，macId组中的alertType为is_notified，并且{{ 1}}完成，然后应选择具有每条记录最大时间戳的相应escalation_status，alertTypeId，macId（即使组的时间戳相同，每组最多一条记录）。

如何获得上述结果。我尝试使用以下查询，但未返回任何内容。实际上，它应返回alertType中的1251基本ID记录。

alert_details_status table having timestamp >30 min compared to present timestamp. So for that alertTypeId ,macId alertType it should return maximum of timestamp for a group having alertTypeId ,macId alertType(i,e 1251)

我想要的结果是：

SELECT * 
FROM   (SELECT t1.*, 
               Row_number() 
                 OVER( 
                   partition BY t1.alerttype, t1.alerttypeid, t1.macid 
                   ORDER BY t1.timestamp DESC) rn 
        FROM   [test].[dbo].[alertdetails] as t1
               RIGHT JOIN [test].[dbo].[alert_details_status] t2 
                      ON t1.macid = t2.macid 
                         AND t1.alerttypeid = t2.alerttypeid 
                         AND t1.alerttype = t2.alerttype 
                         AND t2.is_notified = 'true '
                         AND t2.escalation_status = 'completed' 
        WHERE  ((DATEDIFF(s, '1970-01-01', GETUTCDATE())-(t2.timeStamp/1000))/60)>4400 and t2.alerttypeid IS NULL  ) t 
WHERE  t.rn = 1

如何获得每组具有最大时间戳的每条记录

0 个答案: