mybatis plus字段为null或空字符串把原来的数据也更新了，只需要注解

@ApiModelProperty(value = "头像")
    @TableField(strategy = FieldStrategy.NOT_EMPTY)
    private String url;
 
    @ApiModelProperty(value = "用户名")
    @TableField(strategy = FieldStrategy.NOT_EMPTY)
    private String username;
 
    @ApiModelProperty(value = "用户昵称")
    @TableField(strategy = FieldStrategy.NOT_EMPTY)
    private String nick;
 
    @ApiModelProperty(value = "密码")
    @TableField(strategy = FieldStrategy.NOT_EMPTY)
    private String password;

public enum FieldStrategy {
    IGNORED,
    NOT_NULL,
    NOT_EMPTY,
    DEFAULT;
 
    private FieldStrategy() {
    }
}