spring.datasource.url=jdbc:sqlserver://localhost:1433;databaseName=mydb
spring.datasource.username=user
spring.datasource.password=123456
spring.jpa.database-platform=org.hibernate.dialect.SQLServer2012Dialect

@Configuration
@PropertySource(value = {"classpath:application.properties"})
public class ConfigurationPropertySource {

    private final ConfigurationRepository configurationRepository;

    @Autowired
    public ConfigurationPropertySource(ConfigurationRepository configurationRepository) {
        this.configurationRepository = configurationRepository;
    }

    public String getValue(String key) {
        ApplicationConfiguration configuration = configurationRepository.findOne(key);
        return configuration.getValue();
    }

}