所有DDL（数据定义语言）语句都是使用称为游标的句柄结构执行的。以下示例显示如何创建 员工示例数据库的表。对于其他示例，您需要它们。

在 MySQL 服务器中，表是非常长寿命的对象，并且经常被用不同语言编写的多个应用程序访问。您通常可以使用已经设置好的表，而不是在您自己的应用程序中创建它们。避免一遍又一遍地设置和删除表，因为这是一项昂贵的操作。临时表除外 ，它可以在应用程序中快速创建和删除。

from __future__ import print_function
import mysql.connector
from mysql.connector import errorcode
DB_NAME = 'employees'
TABLES = {}
TABLES['employees'] = (
    "CREATE TABLE `employees` ("
    "  `emp_no` int(11) NOT NULL AUTO_INCREMENT,"
    "  `birth_date` date NOT NULL,"
    "  `first_name` varchar(14) NOT NULL,"
    "  `last_name` varchar(16) NOT NULL,"
    "  `gender` enum('M','F') NOT NULL,"
    "  `hire_date` date NOT NULL,"
    "  PRIMARY KEY (`emp_no`)"
    ") ENGINE=InnoDB")
TABLES['departments'] = (
    "CREATE TABLE `departments` ("
    "  `dept_no` char(4) NOT NULL,"
    "  `dept_name` varchar(40) NOT NULL,"
    "  PRIMARY KEY (`dept_no`), UNIQUE KEY `dept_name` (`dept_name`)"
    ") ENGINE=InnoDB")
TABLES['salaries'] = (
    "CREATE TABLE `salaries` ("
    "  `emp_no` int(11) NOT NULL,"
    "  `salary` int(11) NOT NULL,"
    "  `from_date` date NOT NULL,"
    "  `to_date` date NOT NULL,"
    "  PRIMARY KEY (`emp_no`,`from_date`), KEY `emp_no` (`emp_no`),"
    "  CONSTRAINT `salaries_ibfk_1` FOREIGN KEY (`emp_no`) "
    "     REFERENCES `employees` (`emp_no`) ON DELETE CASCADE"
    ") ENGINE=InnoDB")
TABLES['dept_emp'] = (
    "CREATE TABLE `dept_emp` ("
    "  `emp_no` int(11) NOT NULL,"
    "  `dept_no` char(4) NOT NULL,"
    "  `from_date` date NOT NULL,"
    "  `to_date` date NOT NULL,"
    "  PRIMARY KEY (`emp_no`,`dept_no`), KEY `emp_no` (`emp_no`),"
    "  KEY `dept_no` (`dept_no`),"
    "  CONSTRAINT `dept_emp_ibfk_1` FOREIGN KEY (`emp_no`) "
    "     REFERENCES `employees` (`emp_no`) ON DELETE CASCADE,"
    "  CONSTRAINT `dept_emp_ibfk_2` FOREIGN KEY (`dept_no`) "
    "     REFERENCES `departments` (`dept_no`) ON DELETE CASCADE"
    ") ENGINE=InnoDB")
TABLES['dept_manager'] = (
    "  CREATE TABLE `dept_manager` ("
    "  `emp_no` int(11) NOT NULL,"
    "  `dept_no` char(4) NOT NULL,"
    "  `from_date` date NOT NULL,"
    "  `to_date` date NOT NULL,"
    "  PRIMARY KEY (`emp_no`,`dept_no`),"
    "  KEY `emp_no` (`emp_no`),"
    "  KEY `dept_no` (`dept_no`),"
    "  CONSTRAINT `dept_manager_ibfk_1` FOREIGN KEY (`emp_no`) "
    "     REFERENCES `employees` (`emp_no`) ON DELETE CASCADE,"
    "  CONSTRAINT `dept_manager_ibfk_2` FOREIGN KEY (`dept_no`) "
    "     REFERENCES `departments` (`dept_no`) ON DELETE CASCADE"
    ") ENGINE=InnoDB")
TABLES['titles'] = (
    "CREATE TABLE `titles` ("
    "  `emp_no` int(11) NOT NULL,"
    "  `title` varchar(50) NOT NULL,"
    "  `from_date` date NOT NULL,"
    "  `to_date` date DEFAULT NULL,"
    "  PRIMARY KEY (`emp_no`,`title`,`from_date`), KEY `emp_no` (`emp_no`),"
    "  CONSTRAINT `titles_ibfk_1` FOREIGN KEY (`emp_no`)"
    "     REFERENCES `employees` (`emp_no`) ON DELETE CASCADE"
    ") ENGINE=InnoDB")

前面的代码显示了我们如何将 CREATE语句存储在名为 TABLES. 我们还在名为 的全局变量中定义了数据库DB_NAME，这使您能够轻松地使用不同的模式。

cnx = mysql.connector.connect(user='scott')
cursor = cnx.cursor()

一个 MySQL 服务器可以管理多个 数据库。通常，您指定连接到 MySQL 服务器时要切换到的数据库。此示例在连接时不会连接到数据库，因此它可以确保数据库存在，如果不存在则创建它：

def create_database(cursor):
    try:
        cursor.execute(
            "CREATE DATABASE {} DEFAULT CHARACTER SET 'utf8'".format(DB_NAME))
    except mysql.connector.Error as err:
        print("Failed creating database: {}".format(err))
        exit(1)
try:
    cursor.execute("USE {}".format(DB_NAME))
except mysql.connector.Error as err:
    print("Database {} does not exists.".format(DB_NAME))
    if err.errno == errorcode.ER_BAD_DB_ERROR:
        create_database(cursor)
        print("Database {} created successfully.".format(DB_NAME))
        cnx.database = DB_NAME
    else:
        print(err)
        exit(1)

database我们首先尝试使用连接对象 的属性更改为特定的数据库 cnx。如果有错误，我们检查错误号以检查数据库是否不存在。如果是这样，我们调用该 create_database函数为我们创建它。

对于任何其他错误，应用程序退出并显示错误消息。

在我们成功创建或更改到目标数据库后，我们通过迭代 TABLES字典的项目来创建表：

for table_name in TABLES:
    table_description = TABLES[table_name]
    try:
        print("Creating table {}: ".format(table_name), end='')
        cursor.execute(table_description)
    except mysql.connector.Error as err:
        if err.errno == errorcode.ER_TABLE_EXISTS_ERROR:
            print("already exists.")
        else:
            print(err.msg)
    else:
        print("OK")
cursor.close()
cnx.close()

为了在表已经存在时处理错误，我们通知用户它已经存在。打印了其他错误，但我们继续创建表。（为了便于说明，该示例显示了如何处理 “表已存在”IF NOT EXISTS条件。在实际应用程序中，我们通常会通过使用语句的子句来完全避免错误条件CREATE TABLE。）

输出将是这样的：

Database employees does not exists.
Database employees created successfully.
Creating table employees: OK
Creating table departments: already exists.
Creating table salaries: already exists.
Creating table dept_emp: OK
Creating table dept_manager: OK
Creating table titles: OK

要填充员工表，请使用 员工示例数据库的转储文件。请注意，您只需要在名为 employees_db-dump-files-1.0.5.tar.bz2. 下载转储文件后，执行以下命令，必要时 向mysql命令添加连接选项：

$> tar xzf employees_db-dump-files-1.0.5.tar.bz2
$> cd employees_db
$> mysql employees < load_employees.dump
$> mysql employees < load_titles.dump
$> mysql employees < load_departments.dump
$> mysql employees < load_salaries.dump
$> mysql employees < load_dept_emp.dump
$> mysql employees < load_dept_manager.dump