# PostgreSQL安装与使用

`PostgreSQL`是开源的关系型数据库。

## 一、安装

## 1.1 Mac OS

`Mac OS`使用`homebrew`安装，在`shell`中输入`brew search postgresql`，得到以下输出:

```bash
==> Formulae
postgresql                    postgresql@11                 postgresql@9.5
postgresql@10 ✔               postgresql@9.4                postgresql@9.6
==> Casks
navicat-for-postgresql
```

选择需要安装的版本即可，`@`后为版本号，例如`brew install postgresql@10`安装`PostgreSQL 10`。

### 1.2 Linux

todo

### 1.3 Windows

todo

## 二、配置

### 2.1 Mac OS

如果安装的不是最新版本，则需要自行添加环境变量，以`Postgre 10`为例，需要添加以下环境变量：

```bash
export PATH="/usr/local/opt/postgresql@10/bin:$PATH"
export LDFLAGS="-L/usr/local/opt/postgresql@10/lib"
export CPPFLAGS="-I/usr/local/opt/postgresql@10/include"
export PKG_CONFIG_PATH="/usr/local/opt/postgresql@10/lib/pkgconfig"
```

在添加完成后，在`shell`中输入`brew services`，检查`PostgreSQL`是否运行，如果没有运行，需要运行`PostgreSQL`服务。以`Postgre 10`为例，`shell`输入`brew services start postgresql@10`即可启动服务。

### 2.2 Linux

todo

### 2.3 Windows

todo

## 三、使用

1. `createdb <dbname>`创建数据库；
2. `psql <dbname>`进入数据库控制台；
3. 使用`\password <pass>`为`postgreSQL`用户设置密码；
4. 使用`create user <username>`创建数据库用户；
5. 创建表，用法如下：

   ```sql
    reate table <tablename> (
        column1 datatype,
        column2 datatype,
        column3 datatype,
        .....
        columnN datatype,
        PRIMARY KEY( 一个或多个列 )
    );
   ```
6. 使用`grant all privileges on <tablename> to <username>`将表的所有权限都赋给某用户。
7. todo...


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://sphantix-hang.gitbook.io/timebook/2.-huan-jing-pian/kai-fa-huan-jing-pei-zhi/tong-yong/postgre_sql.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.