摘要：select score as 类别,count(*) as 人数 from (select case when fen>=60 then '及格' else '不及格' end as score from fen ) fen group by score 阅读全文

摘要：弄好系统首次开机，hdmi转vga无信号 决解办法：找到SD卡中config.txt 中hdmi_safe=1系统启动显示成功 进入初始化界面！命令启动初始化界面：sudo raspi-config输入命令sudo apt-get install ttf-wqy-zenhei这条命令安装的是黑体su... 阅读全文