yaoct的博客

首先分析mysql的geometry的存储格式和输入输出格式，再实现mybatis的转换器转换geometry格式。mybatis的配置见。

1.按属性统计，并且将不存在的属性统计为0左连接+count函数。因为count函数不统计null。所以要count（右表属性）postgre示例： select count(e.id) as cnt,d.name as type from district d LEFT JOIN examination_application e ON ST_Intersects(d.position,e.dig_position) <where>

//时间格式2000-07 //SELECT * //FROM `water_monthly_statistics`; //where ((year>2018 and year <2020) or (year=2018 and month>5) or(year=2020 and month<4)) and region_id in(1,2) private Specification<WaterMonthlyStatistics> get.

Given a Weather table, write a SQL query to find all dates' Ids with higher temperature compared to its previous (yesterday's) dates.+---------+------------------+------------------+| Id(INT) | Recor...

题目描述查找所有员工自入职以来的薪水涨幅情况，给出员工编号emp_no以及其对应的薪水涨幅growth，并按照growth进行升序。当前日期'9999-01-01'CREATE TABLE `employees` (`emp_no` int(11) NOT NULL,`birth_date` date NOT NULL,`first_name` varchar(14) NOT NULL,`last...

题目描述对所有员工的当前(to_date='9999-01-01')薪水按照salary进行按照1-N的排名，相同salary并列且按照emp_no升序排列CREATE TABLE `salaries` (`emp_no` int(11) NOT NULL,`salary` int(11) NOT NULL,`from_date` date NOT NULL,`to_date` date NOT ...

摘自https://www.jb51.net/article/74083.htm我们做软件开发的，大部分人都离不开跟数据库打交道，特别是erp开发的，跟数据库打交道更是频繁，由于SQL 不同于与其他编程语言的最明显特征是处理代码的顺序。在大数编程语言中，代码按编码顺序被处理，但是在SQL语言中，第一个被处理的子句是FROM子句，尽管SELECT语句第一个出现，但是几乎总是最后被处理。      每...

The Employee table holds all employees. Every employee has an Id, and there is also a column for the department Id.+----+-------+--------+--------------+| Id | Name | Salary | DepartmentId |+----+-...

The Trips table holds all taxi trips. Each trip has a unique Id, while Client_Id and Driver_Id are both foreign keys to the Users_Id at the Users table. Status is an ENUM type of (‘completed’, ‘cancel...