mysql想实现两列表格相邻行内容互换报错

mysql想实现两列表格相邻行内容互换报错,第1张

如果只是结果集中交换两列:

select name,id from 表名

如果更改表结构

alter table 表名 modify column id int auto_increment after name

比如:

#建立测试表 t1

mysql>create table t1(id int auto_increment,name varchar(20),primary key(id))engine=innodb,default charset=utf8

Query OK, 0 rows affected (0.11 sec)

#插入3条数据

mysql>insert into t1(name) values ("aa"),("bb"),("cc")

Query OK, 3 rows affected (0.00 sec)

Records: 3 Duplicates: 0 Warnings: 0

mysql>select * from t1

+----+------+

| id | name |

+----+------+

| 1 | aa |

| 2 | bb |

| 3 | cc |

+----+------+

3 rows in set (0.00 sec)

#结果集中排列name到id前

mysql>select name,id from t1

+------+----+

| name | id |

+------+----+

| aa | 1 |

| bb | 2 |

| cc | 3 |

+------+----+

3 rows in set (0.00 sec)

#改变表结构,使name在id前

mysql>alter table t1 modify column id int auto_increment after name

Query OK, 3 rows affected (0.19 sec)

Records: 3 Duplicates: 0 Warnings: 0

mysql>select * from t1

+------+----+

| name | id |

+------+----+

| aa | 1 |

| bb | 2 |

| cc | 3 |

+------+----+

3 rows in set (0.00 sec)

mysql>desc t1

+-------+-------------+------+-----+---------+----------------+

| Field | Type | Null | Key | Default | Extra |

+-------+-------------+------+-----+---------+----------------+

| name | varchar(20) | YES | | NULL | |

| id | int(11) | NO | PRI | NULL | auto_increment |

+-------+-------------+------+-----+---------+----------------+

SAXReader

reader

=

new

SAXReader()

Document

doc=reader.read(new

File("src/Cinema.xml"))

Element

eleRoot=doc.getRootElement()

for(Iterator

its=eleRoot.elementIterator()its.hasNext()){

Element

eleCount=(Element)its.next()

Iterator

it=eleCount.elementIterator()

while(it.hasNext()){

Element

eleName=(Element)it.next()

}

用这些代码可以实现从XML中读取数据

然后建立连接用一个实体类用来临时存放SQL数据把

用List<News>存放

Class.forName("oracle.jdbc.OracleDriver")

String

url="jdbc:oracle:thin:@192.168.0.200:1521:tarena"

Connection

con=DriverManager.getConnection(url,"hsd1103","hsd1103")

String

str="insert

into

news

value(?,?,?,?,?)"//问号是对应下面你所要传递的值和

你SQL中的字段值对应

News

news=new

News()

PreparedStatement

stmt=PreparedStatement

pstm

=

con.prepareStatement()

//把xml中的数据放置到sql中

stmt.setInt(1,news.getID())

stmt.setString(2,news.getName)

stmt.setString(3,news.getAcc())

.

.

.

按照这样的方式些就可以了我用的是oracle


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原文地址: http://outofmemory.cn/zaji/8581728.html

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