Question

我有这个查询：

select a.name, count(distinct numClient)
from a
group by a.name;

我想添加另一列，该列将为每行计数前几行的总和：

JONES     3      0
SMITH     5      3
JOHN      10     8
.....
KEN       12     365

可以帮忙吗？我想我必须使用分区，但是对它的理解不太清楚。

Answer 1

您根本不需要子查询：

#include<stdint.h>
#include<stdlib.h>
#include<stdio.h>
void test(uintptr_t *data)
{
    unsigned char raw_data[] = "this is a test data";
    unsigned char *raw = (unsigned char*)malloc(strlen((char*)raw_data));
    memcpy(raw, raw_data, strlen((char*)raw_data)+1);
    *data = (uintptr_t)raw;
}

int main(int argc, char* argv[])
{
    uintptr_t data;

    test(&data);
    printf("%s\n", (char *)data);
    if ((void *)data != NULL)
    {
        free((void *)data);
    }
    return 0;
}

Answer 2

假设有一列指定计算累积总和的顺序，则可以使用

string checkrole = "select RName from [account] where username= '" + TextBoxUser.Text + "'";
SqlCommand roleCom = new SqlCommand(checkrole, con);
string role = roleCom.ExecuteScalar().ToString();
if (role == "Teacher")
{
    Session["New"] = TextBoxUser.Text;
    Session["Username"] = TextBoxUser.Text;
    Response.Redirect("HomeTeacher.aspx");
}
else
{
    Response.Redirect("HomeParent.aspx");
}

使用分区的Oracle SQL查询

2 个答案: