2022-11-29:查找重复的电子邮箱。以下数据中a@b.com是重复的,请写出sql语句。
DROP TABLE IF EXISTS person;
CREATE TABLE person (
id int(11) NOT NULL,
email varchar(255) NOT NULL,
PRIMARY KEY (id...
2022-12-17:订单最多的客户。以下数据,结果输出3。请问sql语句如何写?
DROP TABLE IF EXISTS `orders`;
CREATE TABLE `orders` (
`order_number` int(11) NOT NULL,
`customer_number` int(11) NOT NULL,
...
SELECT
表名 = Case When A.colorder=1 Then D.name Else '' End,
表说明 = Case When A.colorder=1 Then isnull(F.value,'') Else '' End,
字段序号 = A.colorder,
字段名 ...
自定义函数:
1 USE [ExpenseCenter_Fibrogen]
2 GO
3 /****** Object: UserDefinedFunction [dbo].[GetSubordinateTable] Script Date: 2014/10/11 13:24:32 ******/
4 SET ANSI_NULLS ON
5 GO
6 SET ...