メールアドレスとパスワードでログインしようとすると、
Table '(データベース名）.authorities' doesn't exist
というエラーが出た。

この時のテーブル名はuserだったが、
mysql > alter table user rename to authorities;
でauthoritiesに変更。

次に
Unknown column usernameやUnknown column authorityといったエラーが出た。

SecurityConfig.java

package com.example.demo;

import javax.sql.DataSource;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
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.builders.WebSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
import org.springframework.security.crypto.password.PasswordEncoder;


@EnableWebSecurity
@Configuration
public class SecurityConfig extends WebSecurityConfigurerAdapter  {
	@Autowired
	private DataSource dataSource;	

	@Bean
	public PasswordEncoder passwordEncoder() {
		return new BCryptPasswordEncoder();
	}
	
	private static final String USER_SQL = "SELECT"
	+ " email,"
	+ " password,"
	+" true"
	+" FROM"
	+" authorities"
	+" WHERE"
	+" email = ?";
	
	@Override
	public void configure(WebSecurity web) throws Exception {
		web.ignoring().antMatchers("/webjars/**", "/css/**");
	}
	
	@Override
	protected void configure(HttpSecurity http) throws Exception {
		http.authorizeRequests()
		.antMatchers("/webjars/**").permitAll()
		.antMatchers("/css/**").permitAll()
		.antMatchers("/login").permitAll()
		.antMatchers("/signup").permitAll()
		.anyRequest().authenticated();
		
		http.formLogin()
		.loginProcessingUrl("/login")
		.loginPage("/login")
		.failureUrl("/login")
		.usernameParameter("email")
		.passwordParameter("password")
		.defaultSuccessUrl("/home", true);
	}
	
	@Override
	protected void configure(AuthenticationManagerBuilder auth) throws Exception {
		auth.jdbcAuthentication()
		.dataSource(dataSource)
		.usersByUsernameQuery(USER_SQL)
		.passwordEncoder(passwordEncoder());
	}

	
}

上記の、.usernameParameter("email")　.passwordParameter("password")
のところで、column名がusernameとauthorityに固定されてしまうらしい。

カラム名をemail→username、password→authorityに変更
mysql > alter table authorities change email username varchar(50);
mysql > alter table authorities change password authority varchar(100);

SecurityConfig.javaの該当部分も変更。

その後ログイン成功。