Spring boot&Mybatis 启动报错 Failed to auto-configure a DataSource

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APPLICATION FAILED TO START
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Description:

Failed to configure a DataSource: 'url' attribute is not specified and no embedded datasource could be configured.

Reason: Failed to determine a suitable driver class

Action:

Consider the following:
    If you want an embedded database (H2, HSQL or Derby), please put it on the classpath.
    If you have database settings to be loaded from a particular profile you may need to activate it (no profiles are currently active).

解决方法  1：             注解这样写：   

        @SpringBootApplication(exclude= {DataSourceAutoConfiguration.class})

@SpringBootApplication(exclude= {DataSourceAutoConfiguration.class})
public class DemoApplication {

	public static void main(String[] args) {
		SpringApplication.run(DemoApplication.class, args);
	}
}

解决方案 2：

1,。添加如下依赖

     <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
            <!-- 移除嵌入式tomcat插件 不移除会启动报错 -->
            <exclusions>
                <exclusion>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-starter-tomcat</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

2.必须要加否则启动

<dependency>
     <groupId>javax.servlet</groupId>
     <artifactId>javax.servlet-api</artifactId>
</dependency>