INSERT INTO customers VALUES(NULL, 'Fang');

-- 推荐更安全、扩展性更好的方式
INSERT INTO customers(cust_id, cust_name) VALUES(NULL, 'Fang');

-- 进一步，无需插入 AUTO_INCREMENT 属性的列
INSERT INTO customers(cust_name) VALUES('Fang');

-- 插入多条数据，单条语句插入比多次语句性能更高
INSERT INTO customers(cust_name) VALUES('Fang'), ('Quan');

-- 插入检索出的数据
INSERT INTO customers(cust_id, cust_name) SELECT cust_id, cust_name FROM custnew;

-- 拼接字段 Concat()
SELECT Concat(vend_name, ' (', vend_country, ')') FROM vendors ORDER BY vend_name;

-- Trim() 去除空格
SELECT Concat(RTrim(vend_name), ' (', RTrim(vend_country), ')') FROM vendors ORDER BY vend_name;

-- 使用别名 AS
SELECT Concat(RTrim(vend_name), ' (', RTrim(vend_country), ')') AS vend_title FROM vendors ORDER BY vend_name;

-- 执行算术计算
SELECT prod_i， quantity, item_price, quantity*item_price AS expanded_price FROM orderitems WHERE order_num = 20005;

-- 显示数据库
SHOW DATABASES;

-- 选择数据库
USE some_db;

-- 显示表
SHOW TABLES;

-- 显示表的列信息
SHOW COLUMNS FROM some_table;
DESCRIBE some_table;

-- 显示数据库服务器状态信息
SHOW STATUS;

-- 显示授予用户的权限
SHOW GRANTS;

-- 显示服务器错误信息/警告信息
SHOW ERRORS;
SHOW WARNINGS;