1) linkage operation optimization
![点击朗读](/dictall/images/read.gif)
连接运算的优化
2) join operation
![点击朗读](/dictall/images/read.gif)
连接运算
1.
Algorithms of estimating the sizes of query results of selection operations and join operations are designed, and corresponding experiments are implemented, and a clue of further research is given.
设计了用直方图估计选择运算与连接运算结果大小的算法,进行了相应的实验,并提出下一步工作的思路。
3) optimized generation algorithm of connecting line
![点击朗读](/dictall/images/read.gif)
连接线生成优化算法
4) Computing Optimization
![点击朗读](/dictall/images/read.gif)
运算优化
5) Connector operators
![点击朗读](/dictall/images/read.gif)
连接件运算符
6) two-sided concatenation operation
![点击朗读](/dictall/images/read.gif)
双向连接运算
补充资料:不定积分的运算法则
又称为“不定积分的性质”,包含如下两个性质:
(1)设函数f(x)的原函数存在,k是常数,k≠0,则
∫kf(x)dx=k∫f(x)dx
(2)设f(x),g(x)是两个可积分的函数,则
∫[f(x)+g(x)]dx=∫f(x)dx+∫g(x)dx
说明:补充资料仅用于学习参考,请勿用于其它任何用途。
参考词条