学习目标为学习openGauss数据库创建表、插入记录、查询记录和删除表基本使用。
学习内容，部分显示：
课后作业打卡：
1.创建一个表products
create table products(product_id integer,product_name char(30),category char(20));
CREATE TABLE
2.向表中插入数据，采用一次插入一条和多条记录的方式
omm=# insert into products values(1502,'olympus camera','electrncs');
INSERT 0 1
omm=# insert into products values(1601,'lamaze','electrncs'),(1700,'wait interface','toys'),(1666,'harry potter','toys');
INSERT 0 3
3.查询表中所有记录及记录数
omm=# select * from products;
product_id | product_name | category
------------+--------------------------------+----------------------
1502 | olympus camera | electrncs
1601 | olympus camera | electrncs
1601 | lamaze | electrncs
1700 | wait interface | toys
1666 | harry potter | toys
(5 rows)
omm=# select count(*) from products;
count
-------
5
(1 row)
4.查询表中所有category记录，并将查询结果按升序排序
omm=# select category from products order by product_id;
category
----------------------
electrncs
electrncs
electrncs
toys
toys
(5 rows)
5.查询表中category为toys的记录
omm=# select * from products where category= 'toys';
product_id | product_name | category
------------+--------------------------------+----------------------
1700 | wait interface | toys
1666 | harry potter | toys
(2 rows)
6.删除表products
omm=# drop table products;
DROP TABLE
