[MySQL table structure and integrity constraint modification (Alter)]

database TestDb1 There's a table in it your_table, Please follow the instructions , Add appropriate statements in the code file editing window on the right , Table name your_table Change to my_table.

USE TestDb1;

# Please add the appropriate statement in the space below , Table name your_table Change to my_table:
alter table your_table rename to my_table;

Suppose the database MyDb There's a table in it order( Order ) and orderDetail( The order details ) Isometer , The structures of the two tables are as follows: ：

order surface

Field name	data type	remarks
orderNo	char(12)	The order number , Main code
orderDate	date	subscription date
customerNo	char(12)	Customer number , Outer code , And customer.customerNo Corresponding
employeeNo	char(12)	Employee number , Outer code , And employee.employeeNo Corresponding

orderDetail surface

Field name	data type	remarks
orderNo	char(12)	The order number , Main attribute , Outer code , And order.orderNo Corresponding
productNo	char(12)	Product number , Main attribute , Outer code , And product.productNo Corresponding
quantityOrdered	int	Order quantity
orderDate	date	subscription date

notes ： surface orderDetail The main code of is (orderNo,productNo) form

The task of programming is to orderDetail Table to be modified ：

1. orderDetail Tabular orderDate The column is obviously redundant , Because every transaction in the same order occurs on the same day , This date is in the order body table order There are records in , Please delete the column orderDate.
2. The unit price of the product is the content that needs to be recorded in the order details , Please be there. orderDetail Add columns unitPrice To record the unit price of the product :

Field name	data type	remarks
unitPrice	numeric(10,2)	The transaction unit price of the product

Please follow the instructions , Add appropriate statements in the code file editing window on the right , Realize the above programming tasks .

use MyDb;

# Please add the appropriate SQL Code , Implement programming requirements 
# sentence 1： Delete table orderDetail Column in orderDate
alter table orderDetail drop orderDate;
# sentence 2： Add columns unitPrice
alter table orderDetail add column unitPrice numeric(10,2);

database MyDb There's a table in it addressBook( Address book ), The structure is as follows ：

Field name	data type	remarks
serialNo	int	auto number , Main code
name	char(32)	full name
company	char(32)	Work unit
position	char(10)	Position
workPhone	char(16)	Office phone
mobile	char(11)	mobile phone
QQ	int	QQ Number
weixin	char(12)	WeChat ID

The original statement to create the table is as follows ：

1. create table addressBook(
2. serialNo int auto_increment primary key,
3. name char(32),
4. company char(32),
5. position char(10),
6. workPhone char(16),
7. mobile char(11),
8. QQ int,
9. weixin char(12)
10. );

Your programming task is to check the table addressBook Make the following modifications ：

1. take QQ The data type of No. is changed to char(12);
2. Will be listed weixin Change it to wechat.

   use MyDb;
   
   # Please add the appropriate SQL sentence , Implement programming requirements 
   alter table addressBook modify QQ char(12) ;
   alter table addressBook rename column weixin to wechat;