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)...
Look at the results - it will partition the rows and returns all rows, unlike GROUP BY. 回答3 partition by doesn't actually roll up the data. It allows you to reset something on a per group basis. For example, you can get an ordinal column within a group by partitioning on the group...
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...
SQL PARTITION BY用法 业务描述: 1、如下图所示,有一张表,该表存储某一公司某一部门下当前的预算详情。 预算可以进行多次修订,并且每一次修订的版本需要保留,所以每次修改预算都会新增一条数据到该预算信息表,同时CreateTime是操作数据库当时的时间。 2、某一部门下的预算可以通过科目Code进行详细拆分、所以针对该...
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 ...
example.hive.udf; import org.apache.hadoop.hive.ql.exec.UDF; import org.apache.hadoop.io.Text; public final class Lower extends UDF { public Text evaluate(final Text s) { if (s == null) { return null; } return new Text(s.toString().toLowerCase()); } } 继承UDF函数,重写evaluate...
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...
.partitionBy("city") .saveAsTable("dynamic_partition_example") // 停止SparkSession spark.stop() 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 在上述示例中,我们首先创建了一个SparkSession对象,然后设置了相关参数启用动态分区功能。接...
SELECT City AS CustomerCity, CustomerName,amount, ROW_NUMBER() OVER(PARTITION BY city ORDER BY amount DESC) AS [Row Number] FROM [SalesLT].[Orders] For example, in the [Alwar] city, the row with the highest amount (25000.00) is in row 1. As shown below, it ranks rows in the wind...