Linux中nano和vim读可以打开记事文件。
ifdown ens33
ifup ens33
关闭,开启网络
rm -r lesson1
gcc -o code1 code1.c
编译c语言代码
./code1
执行c语言代码
rm -r dir
删除文件夹
mysql> show databases
-> ^C
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| online_edu |
| performance_schema |
| sys |
| test |
+--------------------+
6 rows in set (0.08 sec)
展示数据库
mysql> use test;
Database changed
mysql> create table tb_user(
-> id int comment'编号',
-> name varchar(50) comment'姓名',
-> age int comment'年龄',
-> gender varchar(1) comment'性别'
-> );
使用test数据库,使用tb_user表。
mysql> desc tb_user;
查看表结构。
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课设中遇到的问题:
【异常】JDK21报错NoSuchFieldError: Class com.sun.tools.javac.tree.JCTree$JCImport does not have member fie
[【异常】JDK21报错NoSuchFieldError: Class com.sun.tools.javac.tree.JCTreeJCImport does not have member fie_java: java.lang.nosuchfielderror: class com.sun.to-CSDN博客https://blog.csdn.net/G971005287W/article/details/133350154](https://blog.csdn.net/G971005287W/article/details/133350154 "【异常】JDK21报错NoSuchFieldError: Class com.sun.tools.javac.tree.JCTreeJCImport does not have member fie_java: java.lang.nosuchfielderror: class com.sun.to-CSDN博客")