Welcome

首页 / 软件开发 / .NET编程技术 / ADO.NET Entity Framework(5)esql (二)

ADO.NET Entity Framework(5)esql (二)2010-08-28 cnblogs WXWinteresql函数 统计类

Avg平均值

myContext context = new myContext();
string esql = "SELECT value AVG(it.ItemValue) FROM myContext.DBItemList as it";
ObjectQuery<int> query = context.CreateQuery<int>(esql);
foreach (int n in query)
{
Console.WriteLine(n);
}

/* print:
3
*/

BigCount个数(long)

myContext context = new myContext();
string esql = "SELECT value BigCount(it.ItemValue) FROM myContext.DBItemList as it";
ObjectQuery<long> query = context.CreateQuery<long>(esql);
foreach (long n in query)
{
Console.WriteLine(n);
}

/* print:
15
*/

Count个数(int)

myContext context = new myContext();
string esql = "SELECT value Count(it.ItemValue) FROM myContext.DBItemList as it";
ObjectQuery<int> query = context.CreateQuery<int>(esql);
foreach (int n in query)
{
Console.WriteLine(n);
}

/* print:
15
*/

Max最大值

myContext context = new myContext();
string esql = "SELECT value Max(it.ItemValue) FROM myContext.DBItemList as it";
ObjectQuery<int> query = context.CreateQuery<int>(esql);
foreach (int n in query)
{
Console.WriteLine(n);
}

/* print:
6
*/

Min最小值

myContext context = new myContext();
string esql = "SELECT value Min(it.ItemValue) FROM myContext.DBItemList as it";
ObjectQuery<int> query = context.CreateQuery<int>(esql);
foreach (int n in query)
{
Console.WriteLine(n);
}

/* print:
1
*/

Sum合计

myContext context = new myContext();
string esql = "SELECT value Sum(it.ItemValue) FROM myContext.DBItemList as it";
ObjectQuery<int> query = context.CreateQuery<int>(esql);
foreach (int n in query)
{
Console.WriteLine(n);
}

/* print:
54
*/