创建sql
USE test;
SELECT DATABASE();
SHOW TABLES;
SHOW TABLES FROM mysq1;
CREATE TABLE tb1(
id SMALLINT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
username VARCHAR(20) NOT NULL UNIQUE KEY DEFAULT '',
age TINYINT UNSIGNED,
salary FLOAT(8,2) UNSIGNED NULL
)ENGINE=InnoDB;
SHOW COLUMNS FROM tb1; //查看数据表结构 
