1、在命令行登录指定数据库

2、创建表

CREATE TABLE weather (city            varchar(80),temp_lo         int,           -- low temperaturetemp_hi         int,           -- high temperatureprcp            real,          -- precipitationdate            date
);

PostgreSQL 的注释是：--

MySQL 的注释是：#
3、表的继承

CREATE TABLE cities (name       text,population real,altitude   int     -- (in ft)
);CREATE TABLE capitals (state      char(2)
) INHERITS (cities);

指定“父表”——查询“父表”和“字表”：

SELECT name, altitudeFROM citiesWHERE altitude > 500;name    | altitude
-----------+----------Las Vegas |     2174Mariposa  |     1953Madison   |      845
(3 rows)

ONLY 加“父表”——只查询父表

SELECT name, altitudeFROM ONLY citiesWHERE altitude > 500;name    | altitude
-----------+----------Las Vegas |     2174Mariposa  |     1953
(2 rows)