Skip to content

Commit

Permalink
update
Browse files Browse the repository at this point in the history
  • Loading branch information
xiajieqiong committed Mar 8, 2024
1 parent b1e39e3 commit 23fcbd3
Show file tree
Hide file tree
Showing 4 changed files with 85 additions and 73 deletions.
11 changes: 11 additions & 0 deletions docs/Java/Maven.md
Original file line number Diff line number Diff line change
@@ -0,0 +1,11 @@
## 构建流程

1. clean: 清理, 删除之前编译的 class 文件
2. compile: 编译, 将 java 源程序编译成 class 字节码文件、
3. test: 测试, 自动调用 junit 程序
4. report: 报告, 测试程序执行的结果
5. package:打包, 动态 Web 工程打包 War 包, java 工程打包 jar 包
6. install: 安装, 将打包文件复制到指定位置
7. deploy: 部署, 将动态 Web 工程生成的 war 包复制到 Servlet 容器下

##
1 change: 1 addition & 0 deletions docs/Java/index.md
Original file line number Diff line number Diff line change
@@ -1,2 +1,3 @@
- [正则表达式](./Regex.html)
- [基础](./Base.html)
- [IDEA 快捷键](./Idea-keymap.html)
98 changes: 45 additions & 53 deletions docs/TechnicalTopics/Linux.md
Original file line number Diff line number Diff line change
@@ -1,105 +1,97 @@
[[toc]]

##
## 命令

### cd

#### -

回到切换前的目录
```sh
cd <dir>

#### ..
# 回到切换前的目录
cd -

回到上层目录
# 回到上层目录
cd ..
```

### pwd

### ls

#### -l

长格式显示文件

#### -a

显示隐藏文件

#### -r

逆序显示
```sh
# 长格式显示文件
ls -l

#### -t
# 显示隐藏文件
ls -a

按照时间顺序显示
# 逆序显示
ls -r

#### -R
# 递归显示
ls -R

递归显示
# 按照时间顺序显示
ls -t
```

### mkdir

新建目录

```sh
# 新建目录
mkdir <dir> <dir>
```

#### -p

多层级创建

```sh
# 多层级创建
mkdir -p /<dir>/<dir>/<dir>
```

### rmdir

删除目录(空目录)
删除目录

```sh
rmdir <dir>
```

### rm

删除目录或文件

```sh
rm <dir>
```

#### -r

递归删除

#### -f
# 递归删除
rm <dir> -r

无需确认
# 无需确认
rm <dir> -f
```

### cp

复制文件或目录

#### -v

显示过程

#### 复制文件

```sh
# 文件复制
cp a.txt b.txt
```

#### 复制目录
# 显示过程
cp a.txt b.txt -v

```sh
# 目录复制
cp -r /a /b
```

#### -p

保留原有文件时间
# 保留原有文件时间
cp -p a.txt b.txt

#### -a

保留全部
# 保留全部
cp -a a.txt b.txt
```

### mv

移动文件或文件夹

## man

通过man指令可以查看Linux中的指令帮助、配置文件帮助和编程帮助等信息
48 changes: 28 additions & 20 deletions docs/TechnicalTopics/Mysql.md
Original file line number Diff line number Diff line change
Expand Up @@ -81,7 +81,13 @@ ALTER USER '用户'@'host' IDENTIFIED BY '新密码'
flush privileges
```

## ADD COLUMN
## 查询

### SELECT

## 表结构编辑

### ADD COLUMN

添加表列

Expand All @@ -90,7 +96,7 @@ ALTER TABLE user
ADD COLUMN age int not NULL after name
```

## CHANGE COLUMN
### CHANGE COLUMN

修改表列

Expand All @@ -99,7 +105,7 @@ ALTER TABLE user
CHANGE name1 name VARCHAR(255)
```

## DELETE COLUMN
### DELETE COLUMN

删除表列

Expand All @@ -108,11 +114,19 @@ ALTER TABLE user
DROP COLUMN name;
```

## 数据更新

## UPDATE

更新数据
批量修改时间,统一 +8 小时

```sql
update stat set createdAt = DATE_ADD(createdAt, INTERVAL 8 HOUR);
```

## 连接

## join
### join

内连接, 获取两个表字段匹配关系的记录

Expand All @@ -126,9 +140,11 @@ DROP COLUMN name;
SELECT article.id, article.title, user.name from article left join user on article.user_id = user.id
```

## NOT IN
## 条件

## LIMIT
### NOT IN

### LIMIT

限定返回行数

Expand All @@ -138,7 +154,7 @@ SELECT article.id, article.title, user.name from article left join user on artic
SELECT name from user LIMIT 10
```

## DISTINCT
### DISTINCT

检索不同的行, 去重匹配, 有多个列时, 多个列都相同才会被过滤

Expand All @@ -148,9 +164,9 @@ SELECT name from user LIMIT 10
SELECT DISTINCT name, age from user
```

## Group By
### Group By

## IS NULL 和 IS NOT NULL
### IS NULL 和 IS NOT NULL

对于 NULL 字段 需要使用 IS NULL 和 IS NOT NULL 判断

Expand All @@ -160,7 +176,7 @@ SELECT DISTINCT name, age from user
SELECT name from user where name!='张三' or name IS NULL
```

## Order By
### Order By

排序默认升序(ASC)排序

Expand All @@ -170,18 +186,10 @@ SELECT name from user where name!='张三' or name IS NULL
SELECT name from user Order By age DESC
```

## IFNULL
### IFNULL

用于判断一个表达式是否为 NULL, 如果是 NULL 则返回第二个参数的值

```sql
SELECT IFNULL((SELECT name from user LIMIT 1), 'xjq')
```

## UPDATE

批量修改时间,统一 +8 小时

```sql
update stat set createdAt = DATE_ADD(createdAt, INTERVAL 8 HOUR);
```

0 comments on commit 23fcbd3

Please sign in to comment.