Spark SQL 官方文档中SQL Syntax一节对Grouping Sets语句的描述如下: Groups the rows for each grouping set specified after GROUPING SETS. (... 一些举例) This clause is a shorthand for aUNION ALLwhere each leg of theUNION ALLoperator performs aggregation of each grouping set specified in theGROUPIN...
Groups the rows for each grouping set specified after GROUPING SETS. (... 一些举例) This clause is a shorthand for aUNION ALLwhere each leg of theUNION ALLoperator performs aggregation of each grouping set specified in theGROUPING SETSclause. (... 一些举例) 也即,Grouping Sets语句的作用是指...
If we omit one set of parenthesis from the above query, the meaning changes significantly and we end up separately aggregating by employee and then computing the year and month ROLLUP for all employees. The new GROUPING SETS syntax is available in all of SQL Server 2008 Community Technology ...
Spark SQL 官方文档中 SQL Syntax 一节对 Grouping Sets 语句的描述如下: Groups the rows for each grouping set specified after GROUPING SETS. (... 一些举例) This clause is a shorthand for a UNION ALL where each leg of the UNION ALL operator perfor...
Spark SQL 官方文档中SQL Syntax一节对Grouping Sets语句的描述如下: Groups the rows for each grouping set specified after GROUPING SETS. (… 一些举例) This clause is a shorthand for aUNION ALLwhere each leg of theUNION ALLoperator performs aggregation of each grouping set specified in theGROUPING...
从代码本身可以看到,你只在GROUP BY GROUPING SETS子句里指定需要的分组集——其它的一切都由SQL Server搞定。指定的空括号是所谓的Empty Grouping Set,是跨整个表的聚集。当你看STATISTICS IO输出时,你会发现Sales.SalesOrderHeader只被访问了1次!这是和刚才手工实现的巨大区别。
当此条统计 SQL 加上 ROLLUP 子句后,会在每个分组后面加上一行统计值,其中统计行高位字段显示为 NULL,COUNT 结果用来计算分组内的总记录数。 代码语言:javascript 代码运行次数:0 运行 AI代码解释 mysql>SELECTr1,r2,COUNT(*)->FROMy1->GROUPBYr1,r2WITHROLLUP;+---+---+---+|r1|r2|count(*)|+---+...
Spark SQL 官方文档中SQL Syntax一节对Grouping Sets语句的描述如下: Groups the rows for each grouping set specified after GROUPING SETS. (... 一些举例) This clause is a shorthand for aUNION ALLwhere each leg of theUNION ALLoperator performs aggregation of each grouping set specified in theGROUPIN...
Spark SQL 官方文档中SQL Syntax一节对Grouping Sets语句的描述如下: Groups the rows for each grouping set specified after GROUPING SETS. (... 一些举例) This clause is a shorthand for aUNION ALLwhere each leg of theUNION ALLoperator performs aggregation of each grouping set specified in theGROUPIN...
Rollup Cube Grouping Set使用总结blog.51cto.com/joetang/1680382 其他两个关键字:GROUPING_ID()配合GROUPING()函数 GROUPING SETS,GROUPING__ID,CUBE,ROLLUP 这几个分析函数通常用于OLAP中,不能累加,而且需要根据不同维度上钻和下钻的指标统计,比如,分小时、天、月的UV数。 groupingset 该关键字可以实现同一...