Java基礎(chǔ)學(xué)習(xí)之?dāng)?shù)據(jù)庫連接

數(shù)據(jù)庫的操作mysql
增刪查改

mysql> show databases;
數(shù)據(jù)庫的展示

mysql> use java12
使用數(shù)據(jù)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(chuàng)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(shù)據(jù)

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

mysql> delete from person where age = 20;
Query OK, 1 row affected (0.00 sec)
表格數(shù)據(jù)的刪除

//更新數(shù)據(jù)表中文報(bào)錯(cuò)，因?yàn)閯?chuàng)建數(shù)據(jù)庫的時(shí)候并沒有指定字符編碼
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(chuàng)建一個(gè)可以存儲(chǔ)漢字的數(shù)據(jù)庫

//插入多條記錄報(bào)錯(cuò)
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(shù)據(jù)庫的連接

首先建立驅(qū)動(dòng)：
DriverManager.registerDriver(new Driver());

-----然后建立連接
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(shù)據(jù)的處理
遍歷數(shù)據(jù)并且進(jìn)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(chuàng)建四個(gè)接受的對(duì)象，進(jìn)行數(shù)據(jù)的接受。