In the previous example, we used Group By with CustomerCity column and calculated average, minimum and maximum values. 我们可以将SQL PARTITION BY子句与OVER子句一起使用,以指定需要对其进行聚合的列。 在上一个示例中,我们将“分组依据”与“ CustomerCity”一起使用,并计算了平均值,最小值和最大值。
IIF(SUM(CAST(b.IsFastRefund AS INT)) OVER (PARTITION BY a.InvoiceId) > 0, 1, 0) AS IsFastRefund, (SUM(b.VatAmount) OVER (PARTITION BY a.InvoiceId) / COUNT(1) OVER (PARTITION BY b.ItemId)) AS VatAmount, CAST((SUM(b.VatAmount) OVER (PARTITION BY a.InvoiceId) / COUNT(1)...
AI代码解释 WITHRankedOrdersAS(SELECTorder_id,customer_id,order_date,total_amount,ROW_NUMBER()OVER(PARTITIONBYcustomer_idORDERBYorder_date)ASrow_numFROMorders)SELECTcustomer_id,order_id,order_date,total_amountFROMRankedOrdersWHERErow_num<=2; 这些示例只是SQL数据分析的入门,你可以根据具体的需求进一步深...
并且,表和分区都能够对某个列进行 CLUSTERED BY 操作,将若干个列放入一个桶(bucket)中。也能够利用SORT BY 对数据进行排序。这样能够为特定应用提高性能。详细SQL例如以下: Sql代码 CREATETABLEtest_1(idINT,nameSTRING, city STRING) PARTITIONEDBY(pt STRING) SORTEDBYTEXTFILE ROW FORMAT DELIMITED‘\t’ Hive...
userid=scott/tiger'.One may specify parameters by position before but not after parameters specified by keywords.For example,'sqlldr scott/tiger control=foo logfile=log'is allowed,but'sqlldr scott/tiger control=foo log'is not,even though the ...
ALTER DATABASE example_db SET DATA QUOTA 1073741824; Alter Table 该语句用于对已有的table进行修改。该语句分为三种操作类型:partition、rollup和schema change。Partition是上文提到的复合分区中的第一级分区;rollup是物化索引相关的操作;schema change用来修改表结构。这三种操作不能同时出现在一条ALTER TABLE语句中...
--Example 1: train on entire datasetEXEC train_rxLogIt_per_partition N'SELECTpayment_type, tipped, passenger_count, trip_time_in_secs, trip_distance, d.direct_distanceFROMdbo.nyctaxi_sampleCROSSAPPLY[CalculateDistance](pickup_latitude, pickup_longitude, dropoff_latitude, dropoff_longitude)asd';...
SELECT name, date_modified FROM msdb.dbo.sysjobs ORDER BY date_modified DESC; 執行快照複寫作業以產生快照集: SQL 複製 USE msdb; GO --generate snapshot of publications, for example EXECUTE dbo.sp_start_job N'PUBLISHER-PUBLICATION-SnapshotRepl-1'; GO 執行快照複製作業以產生快照: SQL 複製...
CREATE TABLE range_example ( range_key_column DATE, DATA VARCHAR2 (20), ID INTEGER ) PARTITION BY RANGE (range_key_column) (PARTITION part01 VALUES LESS THAN (TO_DATE ('2008-07-1 00:00:00', 'yyyy-mm-dd hh24:mi:ss')) TABLESPACE tbs01, ...
SELECT LPAD('Page 1',15,'*.')"LPAD example"FROM DUAL; SELECT ename, RPAD('', sal/1000/1,'*')"Salary"FROM emp WHERE deptno=20ORDER BY ename,"Salary"; trim() selecttrim('a'from'ahappy')fromdual; (2)日期函数 1.日期函数