线段树很重要!!! #include<iostream>#include<cstdio>using namespace std;int a[100005];struct node{int l,r,Min,mid;long long sum,add;}s[500010];void pushDown(int idx){ long long tmp = s[idx].add; int
Mysql 优化器之派生条件回移Derived Condition Pushdown详解 派生条件回移优化概述 Mysql 8.0.22之后的版本支持派生条件回移(Derived Condition Pushdown)优化。该优化可以减少派生表处理的行数从而提高查询执行的效率。比方说有如下查询: SELECT * FROM (SELECT i, j FROM t1) AS dt WHER