rollup函数使用sort耗时长,总耗时达到50s(即17号-20号算子的总耗时),(并行度32的情况下),20号算子Vector sort达24s,19号算子Vector Sore Aggregate达9s,18号算子做重分布达10s,17号算子hashagg达到8s。因此需要考虑对rollup类的分析函数考虑使用其它方式进行优化,比如用hashagg替代s
CROSS APPLY is a Microsoft's extension to SQL, which was originally intended to be used with table-valued functions (TVF's). The query above would look like this: ? 1 2 3 4 5 6 7 8 9 SELECT * FROM table1 CROSS APPLY ( SELECT TOP (table1.rowcount) * FROM table2 ORDER BY id ...
The skewed distribution of female participants reflects, in part, the skewed distribution of the number of overall participants. Therefore, we calculate the proportion of each country’s contingent that consists of females. The panel (c) of Figure 1 shows female proportions over time. Aggregate fem...