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Java基礎學習之數據庫連接

數據庫的簡單操作

數據庫的操作mysql
增刪查改

mysql> show databases;
數據庫的展示

mysql> use java12
使用數據庫

mysql> drop table person;
刪除表格

Query OK, 0 rows affected (0.01 sec)

mysql> create table person(age int(4),name varchar(20),telNum varchar(14));
Query OK, 0 rows affected (0.01 sec)

創建表格名為person

mysql> insert into person(age,name,telNum) values(20,"AA","13603711234");
Query OK, 1 row affected (0.02 sec)

插入數據

mysql> update person set telNum = "13838260132" where name = "CC";
Query OK, 1 row affected (0.00 sec)

更新數據

mysql> delete from person where age = 20;
Query OK, 1 row affected (0.00 sec)

表格數據的刪除

//更新數據表中文報錯,因為創建數據庫的時候並沒有指定字符編碼
mysql> update person set name ="張三" where telNum = "18603710987";
ERROR 1366 (HY000): Incorrect string value: ‘\xD5\xC5\xC8\xFD‘ for column ‘name‘
at row 1

創建一個可以存儲漢字的數據庫

//插入多條記錄報錯
mysql> insert into person(age,name,telNum) values(22,"DD","110") (23,"EE","120")
;
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that
corresponds to your MySQL server version for the right syntax to use near ‘(23,"
EE","120")‘ at line 1
Java與數據庫的連接

首先建立驅動:
DriverManager.registerDriver(new Driver());

-----然後建立連接
Connection conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/computer","root","root");
建立SQL語句
Statement statement=(Statement) conn.createStatement();
ResultSet resultSet=statement.executeQuery("select * from user");

數據的處理
遍歷數據並且進行接收

while(resultSet.next()){
String name=resultSet.getString("name");
double heigh=resultSet.getDouble("heigh");
String sex=resultSet.getString("sex");
int weight=resultSet.getInt("weight");
System.out.println("姓名為"+name+"身高為"+heigh+"性別為"+sex);
}
創建四個接受的對象,進行數據的接受。

Java基礎學習之數據庫連接