group by 最后一个时间是多少按多少分组 select count(1), trunc(a.refund_insert_time, 'hh24') + case when to_char(refund_insert_time,'mi') >= '30' then numtodsinterval(30,'minute') else numtodsinterval(0,'minute') end from refund_record a where a.refund_complete_time
Linq to SQL 语法查询(链接查询,子查询 & in操作 & join,分组统计等) 子查询 描述:查询订单数超过5的顾客信息 查询句法: var 子查询 = from c in ctx.Customers where (from o in ctx.Orders group o by o.CustomerID into o where o.Count() > 5 select o.Key).Contains(c.CustomerID) select c; in 操作 描述:查
本工具可实现的效果: 1.读取大文件(大于1GB) 2.根据分隔符分割后的列分组 3.速度快. 4.处理过程中,可以随时停止处理,操作不卡死. 5.有对当前内存的实时监测,避免过多占用内存,影响系统运行. 6.实时显示处理的行数. 处理类代码: using System; using System.Collections.Generic; using System.Diagnostics; using System.IO; using System.Linq; using System.Text
DataTable分组统计: .用两层循环计算,前提条件是数据已经按分组的列排好序的. DataTable dt = new DataTable(); dt.Columns.AddRange(new DataColumn[] { new DataColumn("name", typeof(string)), new DataColumn("sex", typeof(string)), new DataColumn("score", typeof(
1. 斐波那契 from itertools import islice def fib(): a, b = 0, 1 while True: yield a a, b = b, a+b print list(islice(fib(), 5)) # [0, 1, 1, 2, 3] 2. for……else……用法(以查找素数为例) 正常版本: def print_prime(n): for i in xrange(2, n): found = True for j in xrange(2, i)
Mysql 根据时间戳按年月日分组统计create_time时间格式SELECT DATE_FORMAT(create_time,'%Y%u') weeks,COUNT(id) COUNT FROM role GROUP BY weeks;SELECT DATE_FORMAT(create_time,'%Y%m%d') days,COUNT(id) COUNT FROM role GROUP BY days;SELECT DATE_FORMAT(create_time,'%Y%m') month