Question

在MongoDB中如何在聚合中使用$ match和$ not？这是代码，我想用$ not代替$ in

 #include<stdio.h>
    void nest_loop(int n)
    {
        int i,j;
        char k = 'A';
        for(i=n;i>0;i--)
        {
            for(j=n;j>i;j--)
            {
                printf(" ");//print required spaces.
            }
            for(j=0;j<i;j++)
            {
                printf("%c",k+j);//initial char value of k is A and will be incremented by one as looping continues.
            }
            printf("\n");
        }
    }
    int main()
    {
        int n;
        printf("Enter the row number\n");
        scanf("%d",&n);
        nest_loop(n);
        return 0;
    }

Answer 1

您可以查看$nin运算符：

foreach(var predicate in predicates) 
      request = request.Where(predicate);

示例：

$nin selects the documents where:

the field value is not in the specified array or
the field does not exist.

MongoDB使用匹配和非聚合

1 个答案: