> For the complete documentation index, see [llms.txt](https://docs.postgresql.tw/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.postgresql.tw/tutorial/tutorial-sql/tutorial-sql-intro.md).

# 2.1. Introduction \#

This chapter provides an overview of how to use SQL to perform simple operations. This tutorial is only intended to give you an introduction and is in no way a complete tutorial on SQL. Numerous books have been written on SQL, including [\[melt93\]](/bibliography.md#MELT93) and [\[date97\]](/bibliography.md#DATE97). You should be aware that some PostgreSQL language features are extensions to the standard.

In the examples that follow, we assume that you have created a database named `mydb`, as described in the previous chapter, and have been able to start psql.

Examples in this manual can also be found in the PostgreSQL source distribution in the directory `src/tutorial/`. (Binary distributions of PostgreSQL might not provide those files.) To use those files, first change to that directory and run make:

```

$ cd .../src/tutorial
$ make
```

This creates the scripts and compiles the C files containing user-defined functions and types. Then, to start the tutorial, do the following:

```

$ psql -s mydb

...

mydb=> \i basics.sql
```

The `\i` command reads in commands from the specified file. `psql`'s `-s` option puts you in single step mode which pauses before sending each statement to the server. The commands used in this section are in the file `basics.sql`.

***

原文：[PostgreSQL 18.6 Documentation](https://www.postgresql.org/docs/18/tutorial-sql-intro.html)（英文原文，待翻譯）


---

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