best way to connect to the db in spring boot code example

Example 1: connect to database springboot

spring.jpa.hibernate.ddl-auto=update
spring.datasource.url=jdbc:mysql://${MYSQL_HOST:localhost}:3306/db_example
spring.datasource.username=springuser
spring.datasource.password=ThePasswordCopy

Example 2: spring security connect to database

package com.mkyong.config;

import javax.sql.DataSource;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;

@Configuration
@EnableWebSecurity
public class SecurityConfig extends WebSecurityConfigurerAdapter {

	@Autowired
	DataSource dataSource;
	
	@Autowired
	public void configAuthentication(AuthenticationManagerBuilder auth) throws Exception {
		
	  auth.jdbcAuthentication().dataSource(dataSource)
		.usersByUsernameQuery(
			"select username,password, enabled from users where username=?")
		.authoritiesByUsernameQuery(
			"select username, role from user_roles where username=?");
	}	
	
	@Override
	protected void configure(HttpSecurity http) throws Exception {

	  http.authorizeRequests()
		.antMatchers("/admin/**").access("hasRole('ROLE_ADMIN')")
		.and()
		  .formLogin().loginPage("/login").failureUrl("/login?error")
		  .usernameParameter("username").passwordParameter("password")
		.and()
		  .logout().logoutSuccessUrl("/login?logout")
		.and()
		  .exceptionHandling().accessDeniedPage("/403")
		.and()
		  .csrf();
	}
}
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