Spring Boot通过实体类自动创建表时出现创建不上的情况

今天药忘吃喽~ 2022-05-28 04:28 214阅读 0赞

# **         Spring Boot通过实体类自动创建表时出现创建不上的情况 ** #

###     ###

### **  原因1：** ###

### **        启动类和实体类的包命名问题，但是在2.0版本以上的初始化中，一般根目录和与启动类类名相同的包下会有一个启动类(也就是两个启动类)** ###

## **  解决方案1：** ##

**       启动类的包名是com.lihao(根)**

**          实体类包名的命名必须是com.lihao.domain或者com.lihao.entity,这样就可以了**

### **    原因2：** ###

### **        mysql的可视化工具的问题，例如Navicat、SQLyog的问题** ###

## **    ** ##

## **    解决方案2：** ##

现在cmd命令行中创建同名的表，判断是否是这个原因，然后 重启mysql的工具 即可

## **本人代码示例：** ##

###  **1、application.yml代码：** ###

spring: thymeleaf: mode: HTML
    
      datasource: driver-class-name: com.mysql.jdbc.Driver
        url: jdbc:mysql://localhost:3306/spring_boot?useUnicode=true&characterEncoding=utf-8
        username: root
        password: 123456
      jpa: hibernate: ddl-auto: create
        show-sql: true logging: level: root: info
         com.atlihao: debug
      file: log/my.log

**2、User类的代码：**

package com.lihao.domain;
    
    import javax.persistence.Entity;
    import javax.persistence.GeneratedValue;
    import javax.persistence.GenerationType;
    import javax.persistence.Id;
    
    @Entity
    public class User {
        @Id
        @GeneratedValue(strategy = GenerationType.AUTO)
        private long id;
        private String username;
        private String password;
        private int phone;
        private String email;
    
        public User() {
        }
    
        public long getId() {
            return id;
        }
    
        public void setId(long id) {
            this.id = id;
        }
    
        public String getUsername() {
            return username;
        }
    
        public void setUsername(String username) {
            this.username = username;
        }
    
        public String getPassword() {
            return password;
        }
    
        public void setPassword(String password) {
            this.password = password;
        }
    
        public int getPhone() {
            return phone;
        }
    
        public void setPhone(int phone) {
            this.phone = phone;
        }
    
        public String getEmail() {
            return email;
        }
    
        public void setEmail(String email) {
            this.email = email;
        }
    
        @Override
        public String toString() {
            return "User{" +
                    "id=" + id +
                    ", username='" + username + '\'' +
                    ", password='" + password + '\'' +
                    ", phone=" + phone +
                    ", email='" + email + '\'' +
                    '}';
        }
    }

**成功结果：**

**  只要run的过程中能出现类似以下的的代码，即表示为成功！**

Hibernate: drop table if exists hibernate\_sequence  
Hibernate: drop table if exists user  
Hibernate: create table hibernate\_sequence (next\_val bigint) engine=MyISAM  
Hibernate: insert into hibernate\_sequence values ( 1 )

Hibernate: create table user (id bigint not null, email varchar(255), password varchar(255), phone integer not null, username varchar(255), primary key (id)) engine=MyISAM

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[20180329152425782]: /images/20220528/51a3b7e21c814d19abad0d0d7638c49b.png