openGauss每日一练第 1天|创建表，插入记录，删除记录

学习目标

学习openGauss数据库创建表、插入记录、查询记录和删除表基本使用

—创建表

CREATE TABLE products  
( product_id integer,  
product_name char(10),  
category char(10)  
 ) ;

—插入数据

INSERT INTO products (product_id, product_name, category) VALUES (1502, ‘olympus camera’,‘electrncs’);  

—长度不够，修改字段长度后再插入

alter table products MODIFY product_name char(20);  

INSERT INTO products (product_id, product_name, category) VALUES (1502, ‘olympus camera’,‘electrncs’);  

select * from products;  

INSERT INTO products (product_id, product_name, category) VALUES (1601, ‘lamaze’,‘toys’),(1700, ‘wait interface’,‘Books’),(1666, ‘harry potter’,‘toys’);  

—查询表中所有记录及记录数

select count(*) from products;  

select * from products;  

—查询表中所有category记录，并将查询结果按升序排序

select * from products order by category;  

—查询表中category为toys的记录

select * from products where category=‘toys’;  

—删除表products

drop table products;