From 1a776e3e9d8c3f49d22e7759f7d968336f242d95 Mon Sep 17 00:00:00 2001 From: Gui ze yu <2970307356@qq.com> Date: Sun, 19 Feb 2023 23:34:56 +0800 Subject: [PATCH] =?UTF-8?q?=E4=BD=9C=E4=B8=9A?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- ...5\345\217\245\347\273\203\344\271\240 .md" | 314 ++++++++++++++++++ 1 file changed, 314 insertions(+) create mode 100644 "09\346\241\202\346\263\275\347\205\234/DDL\345\222\214DML\350\257\255\345\217\245\347\273\203\344\271\240 .md" diff --git "a/09\346\241\202\346\263\275\347\205\234/DDL\345\222\214DML\350\257\255\345\217\245\347\273\203\344\271\240 .md" "b/09\346\241\202\346\263\275\347\205\234/DDL\345\222\214DML\350\257\255\345\217\245\347\273\203\344\271\240 .md" new file mode 100644 index 0000000..f5bbb45 --- /dev/null +++ "b/09\346\241\202\346\263\275\347\205\234/DDL\345\222\214DML\350\257\255\345\217\245\347\273\203\344\271\240 .md" @@ -0,0 +1,314 @@ +## 第1题 + +1、创建数据库test01_market + +2、创建表格customers + +| 字段名 | 数据类型 | +| --------- | ----------- | +| c_num | int（11） | +| c_name | varchar(50) | +| c_contact | varchar(50) | +| c_city | varchar(50) | +| c_birth | date | + +**要求3：**将c_contact字段移动到c_birth字段后面 + +**要求4：**将c_name字段数据类型改为 varchar(70) + +**要求5：**将c_contact字段改名为c_phone + +**要求6：**增加c_gender字段到c_name后面，数据类型为char(1) + +**要求7：**将表名改为customers_info + +**要求8：**删除字段c_city + +```mysql +创建数据库test01_market： +mysql> create database test01_market; +查看所有数据库： +mysql> show databases; ++--------------------+ +| Database | ++--------------------+ +| information_schema | +| mysql | +| performance_schema | +| sys | +| test01_market | ++--------------------+ +5 rows in set (0.00 sec) +使用test01_market数据库： +mysql> use test01_market +Database changed +创建表格customers： +mysql> create table customers( + -> c_num int(11) , + -> c_name varchar(50) , + -> c_contact varchar(50) , + -> c_city varchar(50) , + -> c_birth date + -> ) comment 'customers' ; +Query OK, 0 rows affected (0.06 sec) +将c_contact字段移动到c_birth字段后面： +mysql> Alter table customers modify c_contact varchar(50) after c_birth ; +Query OK, 0 rows affected (0.10 sec) +Records: 0 Duplicates: 0 Warnings: 0 +查看调整后的结构： +mysql> desc customers; ++-----------+-------------+------+-----+---------+-------+ +| Field | Type | Null | Key | Default | Extra | ++-----------+-------------+------+-----+---------+-------+ +| c_num | int(11) | YES | | NULL | | +| c_name | varchar(50) | YES | | NULL | | +| c_city | varchar(50) | YES | | NULL | | +| c_birth | date | YES | | NULL | | +| c_contact | varchar(50) | YES | | NULL | | ++-----------+-------------+------+-----+---------+-------+ +5 rows in set (0.00 sec) +将c_name字段数据类型改为 varchar(70)： +mysql> Alter table customers modify c_name varchar(70); +Query OK, 0 rows affected (0.02 sec) +Records: 0 Duplicates: 0 Warnings: 0 +查看调整后的结构： +mysql> desc customers; ++-----------+-------------+------+-----+---------+-------+ +| Field | Type | Null | Key | Default | Extra | ++-----------+-------------+------+-----+---------+-------+ +| c_num | int(11) | YES | | NULL | | +| c_name | varchar(70) | YES | | NULL | | +| c_city | varchar(50) | YES | | NULL | | +| c_birth | date | YES | | NULL | | +| c_contact | varchar(50) | YES | | NULL | | ++-----------+-------------+------+-----+---------+-------+ +5 rows in set (0.00 sec) +将c_contact字段改名为c_phone: +mysql> Alter table customers change c_contact c_phone varchar(50); +Query OK, 0 rows affected (0.03 sec) +Records: 0 Duplicates: 0 Warnings: 0 +查看调整后的结构： +mysql> desc customers; ++---------+-------------+------+-----+---------+-------+ +| Field | Type | Null | Key | Default | Extra | ++---------+-------------+------+-----+---------+-------+ +| c_num | int(11) | YES | | NULL | | +| c_name | varchar(70) | YES | | NULL | | +| c_city | varchar(50) | YES | | NULL | | +| c_birth | date | YES | | NULL | | +| c_phone | varchar(50) | YES | | NULL | | ++---------+-------------+------+-----+---------+-------+ +5 rows in set (0.00 sec) +增加c_gender字段到c_name后面，数据类型为char(1): +mysql> Alter table customers add c_gender char(1) after c_name; +Query OK, 0 rows affected (0.09 sec) +Records: 0 Duplicates: 0 Warnings: 0 +查看调整后的结构： +mysql> desc customers; ++----------+-------------+------+-----+---------+-------+ +| Field | Type | Null | Key | Default | Extra | ++----------+-------------+------+-----+---------+-------+ +| c_num | int(11) | YES | | NULL | | +| c_name | varchar(70) | YES | | NULL | | +| c_gender | char(1) | YES | | NULL | | +| c_city | varchar(50) | YES | | NULL | | +| c_birth | date | YES | | NULL | | +| c_phone | varchar(50) | YES | | NULL | | ++----------+-------------+------+-----+---------+-------+ +6 rows in set (0.00 sec) +将表名改为customers_info: +mysql> Alter table customers rename to customers_info; +Query OK, 0 rows affected (0.03 sec) +查看现有表格： +mysql> show tables; ++-------------------------+ +| Tables_in_test01_market | ++-------------------------+ +| customers_info | ++-------------------------+ +1 row in set (0.00 sec) +删除字段c_city： +mysql> Alter table customers_info drop c_city; +Query OK, 0 rows affected (0.08 sec) +Records: 0 Duplicates: 0 Warnings: 0 +查看表结构： +mysql> desc customers_info; ++----------+-------------+------+-----+---------+-------+ +| Field | Type | Null | Key | Default | Extra | ++----------+-------------+------+-----+---------+-------+ +| c_num | int(11) | YES | | NULL | | +| c_name | varchar(70) | YES | | NULL | | +| c_gender | char(1) | YES | | NULL | | +| c_birth | date | YES | | NULL | | +| c_phone | varchar(50) | YES | | NULL | | ++----------+-------------+------+-----+---------+-------+ +5 rows in set (0.00 sec) +``` + +## 第2题 + +1、创建数据库test02_library + +2、创建表格books + +| 字段名 | 字段说明 | 数据类型 | 允许为空 | 唯一 | +| ------- | -------- | ------------- | -------- | ---- | +| b_id | 书编号 | int(11) | 否 | 是 | +| b_name | 书名 | varchar（50） | 否 | 否 | +| authors | 作者 | varchar(100) | 否 | 否 | +| price | 价格 | float | 否 | 否 | +| pubdate | 出版日期 | year | 否 | 否 | +| note | 说明 | varchar(100) | 是 | 否 | +| num | 库存 | int(11) | 否 | 否 | + +3、向books表中插入记录 + +1） 指定所有字段名称插入第一条记录 + +2）不指定字段名称插入第二记录 + +3）同时插入多条记录（剩下的所有记录） + +| b_id | b_name | authors | price | pubdate | note | num | +| ---- | ------------- | --------------- | ----- | ------- | -------- | ---- | +| 1 | Tal of AAA | Dickes | 23 | 1995 | novel | 11 | +| 2 | EmmaT | Jane lura | 35 | 1993 | joke | 22 | +| 3 | Story of Jane | Jane Tim | 40 | 2001 | novel | 0 | +| 4 | Lovey Day | George Byron | 20 | 2005 | novel | 30 | +| 5 | Old land | Honore Blade | 30 | 2010 | law | 0 | +| 6 | The Battle | Upton Sara | 30 | 1999 | medicine | 40 | +| 7 | Rose Hood | Richard haggard | 28 | 2008 | cartoon | 28 | + +4、将小说类型(novel)的书的价格都增加5。 + +5、将名称为EmmaT的书的价格改为40。 + +6、删除库存为0的记录 + +```mysql +创建数据库test02_library： +mysql> create database test02_library; +Query OK, 1 row affected (0.01 sec) +创建表格books： + +``` + + + +## 第3题 + +1、创建数据库test03_bookstore + +2、创建book表 + +```mysql ++----------+--------------+------+-----+---------+----------------+ +| Field | Type | Null | Key | Default | Extra | ++----------+--------------+------+-----+---------+----------------+ +| id | int(11) | NO | PRI | NULL | auto_increment | +| title | varchar(100) | NO | | NULL | | +| author | varchar(100) | NO | | NULL | | +| price | double(11,2) | NO | | NULL | | +| sales | int(11) | NO | | NULL | | +| stock | int(11) | NO | | NULL | | +| img_path | varchar(100) | NO | | NULL | | ++----------+--------------+------+-----+---------+----------------+ +``` + +尝试添加部分模拟数据，参考示例如下： + +```mysql ++----+-------------+------------+-------+-------+-------+----------------------------+ +| id | title | author | price | sales | stock | img_path | ++----+-------------+------------+-------+-------+-------+-----------------------------+ +| 1 | 解忧杂货店 | 东野圭吾 | 27.20 | 102 | 98 | upload/books/解忧杂货店.jpg | +| 2 | 边城 | 沈从文 | 23.00 | 102 | 98 | upload/books/边城.jpg | ++----+---------------+------------+-------+-------+-------+----------------------------+ +``` + +3、创建用户表users，并插入数据 + +```mysql ++----------+--------------+------+-----+---------+----------------+ +| Field | Type | Null | Key | Default | Extra | ++----------+--------------+------+-----+---------+----------------+ +| id | int(11) | NO | PRI | NULL | auto_increment | +| username | varchar(100) | NO | UNI | NULL | | +| password | varchar(100) | NO | | NULL | | +| email | varchar(100) | YES | | NULL | | ++----------+--------------+------+-----+---------+----------------+ +``` + +尝试添加部分模拟数据，参考示例如下： + +```mysql ++----+----------+----------------------------------+--------------------+ +| id | username | password | email | ++----+----------+----------------------------------+--------------------+ +| 1 | admin | 112233 | admin@mxdx.com | ++----+----------+----------------------------------+--------------------+ +``` + +4、创建订单表orders + +```mysql ++--------------+--------------+------+-----+---------+-------+ +| Field | Type | Null | Key | Default | Extra | ++--------------+--------------+------+-----+---------+-------+ +| id | varchar(100) | NO | PRI | NULL | | +| order_time | datetime | NO | | NULL | | +| total_count | int(11) | NO | | NULL | | +| total_amount | double(11,2) | NO | | NULL | | +| state | int(11) | NO | | NULL | | +| user_id | int(11) | NO | MUL | NULL | | ++--------------+--------------+------+-----+---------+-------+ +``` + +尝试添加部分模拟数据，参考示例如下： + +```mysql ++----------------+---------------------+-------------+--------------+-------+---------+ +| id | order_time | total_count | total_amount | state | user_id | ++----------------+---------------------+-------------+--------------+-------+---------+ +| 15294258455691 | 2018-06-20 00:30:45 | 2 | 50.20 | 0 | 1 | ++----------------+---------------------+-------------+--------------+-------+---------+ +``` + +5、创建订单明细表order_items + +```mysql ++----------+--------------+------+-----+---------+----------------+ +| Field | Type | Null | Key | Default | Extra | ++----------+--------------+------+-----+---------+----------------+ +| id | int(11) | NO | PRI | NULL | auto_increment | +| count | int(11) | NO | | NULL | | +| amount | double(11,2) | NO | | NULL | | +| title | varchar(100) | NO | | NULL | | +| author | varchar(100) | NO | | NULL | | +| price | double(11,2) | NO | | NULL | | +| img_path | varchar(100) | NO | | NULL | | +| order_id | varchar(100) | NO | MUL | NULL | | ++----------+--------------+------+-----+---------+----------------+ +``` + +尝试添加部分模拟数据，参考示例如下： + +```mysql ++----+-------+--------+---------+---------+-------+----------------+----------------+ +| id |count| amount| title | author | price | img_path | order_id | ++----+-------+--------+------------+----------+-------+----------------+----------------+ +| 1 | 1 | 27.20| 解忧杂货店 | 东野圭吾 | 27.20 | static/img/default.jpg|15294258455691 | +| 2 | 1 | 23.00| 边城 | 沈从文 | 23.00 | static/img/default.jpg|15294258455691 | ++----+-------+--------+------------+----------+-------+------------+----------------+ +``` + +参考答案： + +```mysql +创建数据库test03_bookstore： +mysql> create database test03_bookstore; +Query OK, 1 row affected (0.01 sec) +创建book表： + +``` + -- Gitee