经纬度坐标 - 经纬度在mysql数据库中如何存储？

有一个要求是不能用double类型，float类型也不能用。那么在mysql中使用什么样的类型存储经纬度比较合适呢？ 如果要存为varchar类型，php中两者该如何转换呢？如果存为int类型，是否要使用bigint，还...

From [MySQLdiscussion group] 2017-04-17 13:26:43 0  3  1576

No permission to access localhost/adminer

When I enter localhost/adminer, the web page displays You don't have permission to access /adminer/ on this se...

From [MySQLdiscussion group] 2018-05-20 16:30:33 0  2  1572

mysql里concat函数和 ‘’|‘’ 符号一起用是表示什么？

比如像这种：concat(t4.name,t4.pinyin,t1.trader)|t4.name

From [MySQLdiscussion group] 2017-04-17 15:35:51 0  1  1567

What is Hadoop used for, what are its main application scenarios and fields, and what are its core problems to be solved? How can we personally

What is Hadoop used for? What are its main application scenarios and application fields? What are the core pro...

From [MySQLdiscussion group] 2020-09-24 16:31:30 0  1  1566

How to test whether PDO calling method is successful

When using PDO, the database connection is normal, but when running this code, the page displays neither resul...

From [MySQLdiscussion group] 2019-08-03 19:08:25 0  2  1563

#1045 Unable to log in to MySQL server?

#1045 Unable to log in to MySQL server, how to solve it

From [MySQLdiscussion group] 2017-12-03 21:50:17 0  3  1560

I want to learn and master a technology well. Please give me some pointers on the path that everyone has taken. It will save me the pain of detours and pitfalls. I can learn by myself and learn by myself.

First, a summary of self-study. The second is to reduce the learning costs of others. The third is others’ rev...

From [MySQLdiscussion group] 2020-09-25 10:38:02 0  1  1557

事务 - mysql共享锁lock in share mode的实际使用场景

看了MySQL的官方文档: 关于锁定对象的部分 分两种锁共享锁: SELECT ... LOCK IN SHARE MODE排它锁: SELECT ... FOR UPDATE 其中排他锁这个场景大家都知道, 就是多个s...

From [MySQLdiscussion group] 2017-04-17 16:41:00 0  1  1551

centos7无法自启动 mysql

阿里云ECS 安装了mysql 5.6，使用 systemctl start mysql成功启动mysql，可使用 systemctl enable mysql将mysql加入到开机自启动，可却报错： {代码...} 使...

From [MySQLdiscussion group] 2017-04-17 14:52:23 0  4  1544

Why does MYSQL cascade update fail? Any advice?

use my_foreign;create table myforeign2(id int primary key auto_increment,name varchar(20) not null,c_id int,fo...

From [MySQLdiscussion group] 2018-06-21 17:56:33 0  0  1536

elasticsearch - Elastisearch怎么求查询结果的交集，如MYSQL的interset

1.查询20151216-17所有的名字 {代码...} 2.查询20151217-18所有的名字 {代码...} 如果在mysql中可用如下的语句求得这两天name的交集 {代码...} Elastisearch中怎么...

From [MySQLdiscussion group] 2017-04-17 15:58:47 0  2  1528

Why doesn't it jump when I enter refresh? Ask God for advice!

<?php header('content-type:text/html;charset=utf-8'); if(isset($_post['submit'])){ $user...

From [MySQLdiscussion group] 2017-11-20 15:07:04 0  1  1520

MySQL timestamp的默认值怎么设置？

目前有三种思路： 使用最小时间：1970-01-01 08:00:01，范围是1970-01-01 08:00:01 ~ 2038-01-19 11:14:07(时区)，参考。 使用当前时间，CURRENT_TIMEST...

From [MySQLdiscussion group] 2017-04-17 16:12:49 0  4  1520

初学python，准备学习做个restful api server，现在有些困惑

在网上看到个教程from flask import Flask, jsonify app = Flask(__name__) tasks =&nb...

From [MySQLdiscussion group] 2016-11-12 11:29:35 0  2  1512

java - Mybatis database multi-table related paging problem

For example: there are two entity classes User and Address {code...} Database: {code...} Mybatis mapping confi...

From [MySQLdiscussion group] 2017-06-10 09:49:39 0  6  1509