我试图在包管理器控制台中使用“update-database”命令更新我的数据库,但我遇到了这种错误:
The child/dependent side could not be determined for the one-to-one
relationship between 'Country.CapitalCity' and 'CapitalCity.Country'. To
identify the child/dependent side of the relationship, configure the foreign
key property. If these navigations should not be part of the same
relationship configure them without specifying the inverse. See
http://go.microsoft.com/fwlink/?LinkId=724062 for more details.
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我的模型类如下所示:
public class Country
{
public int ID { get; set; }
public string Name { get; set; }
public long Population { get; set; }
public int CapitalCityID …Run Code Online (Sandbox Code Playgroud) 请在否决票之前写下原因或搁置问题或其他...
我创建了简单的 spring-boot 应用程序,但由于某种原因无法映射视图,并且出现以下错误:
o.s.web.servlet.PageNotFound - No mapping for GET /WEB-INF/views/welcome.jsp
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此语句后出现问题:
return "welcome";
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这是pom.xml文件:
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.example</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>demo</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.1.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
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我的文件夹结构如下所示:
这是WelcomeController …