急求一个跟数据库相连的小程序,谢谢各位大侠!
发布网友
发布时间：2022-05-14 11:26
共4个回答
热心网友
时间：2023-10-15 13:14
<%
Response.Expires = -1
Response.ExpiresAbsolute = Now() - 1
Response.cachecontrol = "no-cache" ' 清除缓存，根据需要使用
On Error Resume Next '忽略错误，如要调试程序，请先注释掉
dim dbname,conn,connstr
dbname="data.meb" ' 数据库文件名路经
set conn = server.createobject("adodb.connection")
connstr="provider=microsoft.jet.oledb.4.0;data source=" & server.mappath(dbname)
conn.open connstr
%>
asp+sqlserver
<%
Response.Expires = -1
Response.ExpiresAbsolute = Now() - 1
Response.cachecontrol = "no-cache" ' 清除缓存，根据需要使用
Dim ConnStr
connstr="driver={SQL Server};server=.;UID=sa;PWD=123456;database=database" ' 连接字符串，根据自己情况修改
On Error Resume Next '忽略错误，如要调试程序，请先注释掉
Set conn = Server.CreateObject("ADODB.Connection")
conn.open ConnStr
If Err Then
err.Clear
Set Conn = Nothing
Response.Write "数据库连接出错，请检查连接字串。"'注释，需要把这几个字翻译成英文。
Response.End
End If
%>
因为不知道你用什么语言，用什么数据库，就写这两个常用的，希望对你有帮助
热心网友
时间：2023-10-15 13:14
热心网友
时间：2023-10-15 13:15
package learn;
import java.io.PrintWriter;
import java.sql.*;
import java.util.*;
public class OracleConnectionManager {
private DBConnectionManager connMgr;
private final String poolName="Oracle";
private Connection conn;
public OracleConnectionManager() {
String userID = "system";
String password = "manager";
String JDBCDriver = "oracle.jdbc.driver.OracleDriver";
String JDBCDriverType = "jdbc:oracle:thin";
String DBHost = "127.0.0.1";
String Port = "1521";
String SID="sid";
String url = JDBCDriverType+":@"+DBHost + ":" + Port + ":" +SID;
connMgr = DBConnectionManager.getInstance();
if (DBConnectionManager.clients == 1){
connMgr.init(poolName, JDBCDriver, url, userID, password);
connMgr.init("egongOracle", JDBCDriver, JDBCDriverType+":@110.7.6.22:1521:egong", "abcusername", "abcpasswd");
}
}
public Connection getConnection() {
return (conn=connMgr.getConnection(poolName));
}
public Connection getConnection(String newOracle) {
return (conn=connMgr.getConnection(newOracle));
}
public void freeConnection() {
connMgr.freeConnection(poolName,conn);
}
public void freeConnection(String newOracle) {
connMgr.freeConnection(newOracle,conn);
}
}
class DBConnectionManager {
static private DBConnectionManager instance=null; // The single instance
static public int clients=0;
private Vector drivers = new Vector();
private PrintWriter log;
private Hashtable pools = new Hashtable();
private final int MAX_CONN = 1000;
/**
* Returns the single instance, creating one if it′s the
* first time this method is called.
*
* @return DBConnectionManager The single instance.
*/
static synchronized public DBConnectionManager getInstance() {
if (instance == null) {
instance = new DBConnectionManager();
}
clients++;
return instance;
}
/**
* A private constructor since this is a Singleton
*/
private DBConnectionManager() {
// init();
}
/**
* Returns a connection to the named pool.
*
* @param name The pool name as defined in the properties file
* @param con The Connection
*/
public void freeConnection(String name, Connection con) {
DBConnectionPool pool = (DBConnectionPool) pools.get(name);
if (pool != null) {
pool.freeConnection(con);
}
}
/**
* Returns an open connection. If no one is available, and the max
* number of connections has not been reached, a new connection is
* created.
*
* @param name The pool name as defined in the properties file
* @return Connection The connection or null
*/
public Connection getConnection(String name) {
DBConnectionPool pool = (DBConnectionPool) pools.get(name);
if (pool != null) {
return pool.getConnection();
}
return null;
}
/**
* Returns an open connection. If no one is available, and the max
* number of connections has not been reached, a new connection is
* created. If the max number has been reached, waits until one
* is available or the specified time has elapsed.
*
* @param name The pool name as defined in the properties file
* @param time The number of milliseconds to wait
* @return Connection The connection or null
*/
public Connection getConnection(String name, long time) {
DBConnectionPool pool = (DBConnectionPool) pools.get(name);
if (pool != null) {
return pool.getConnection(time);
}
return null;
}
/**
* Closes all open connections and deregisters all drivers.
*/
public synchronized void release() {
// Wait until called by the last client
if (--clients != 0) {
return;
}
Enumeration allPools = pools.elements();
while (allPools.hasMoreElements()) {
DBConnectionPool pool = (DBConnectionPool) allPools.nextElement();
pool.release();
}
Enumeration allDrivers = drivers.elements();
while (allDrivers.hasMoreElements()) {
Driver driver = (Driver) allDrivers.nextElement();
try {
DriverManager.deregisterDriver(driver);
log("Deregistered JDBC driver " + driver.getClass().getName());
}
catch (SQLException e) {
log(e, "Can′t deregister JDBC driver: " + driver.getClass().getName());
}
}
log.close();
}
/**
* Creates instances of DBConnectionPool based on the properties.
* A DBConnectionPool can be defined with the following properties:
* <PRE>
* <poolname>.url The JDBC URL for the database
* <poolname>.user A database user (optional)
* <poolname>.password A database user password (if user specified)
* <poolname>.maxconn The maximal number of connections (optional)
* </PRE>
*
* @param props The connection pool properties
*/
private void createPools(String poolName, String url, String user, String password, int max) {
/*
Enumeration propNames = props.propertyNames();
while (propNames.hasMoreElements()) {
String name = (String) propNames.nextElement();
if (name.endsWith(".url")) {
String poolName = name.substring(0, name.lastIndexOf("."));
String url = props.getProperty(poolName + ".url");
if (url == null) {
log("No URL specified for " + poolName);
continue;
}
String user = props.getProperty(poolName + ".user");
String password = props.getProperty(poolName + ".password");
String maxconn = props.getProperty(poolName + ".maxconn", "0");
int max;
try {
max = Integer.valueOf(maxconn).intValue();
}
catch (NumberFormatException e) {
log("Invalid maxconn value " + maxconn + " for " + poolName);
max = 0;
}
DBConnectionPool pool =
new DBConnectionPool(poolName, url, user, password, max);
pools.put(poolName, pool);
log("Initialized pool " + poolName);
}
}
*/
DBConnectionPool pool =
new DBConnectionPool(poolName, url, user, password, max);
pools.put(poolName, pool);
log("Initialized pool " + poolName);
}
public void init(String poolName, String driver, String url, String user, String passwd) {
init(poolName, driver, url, user, passwd, MAX_CONN);
}
/**
* Loads properties and initializes the instance with its values.
*/
public void init(String poolName, String driver, String url, String user, String passwd, int maxconn) {
/*
InputStream is = getClass().getResourceAsStream("/db.properties");
Properties dbProps = new Properties();
try {
dbProps.load(is);
}
catch (Exception e) {
System.err.println("Can′t read the properties file. " +
"Make sure db.properties is in the CLASSPATH");
return;
}
String logFile = dbProps.getProperty("logfile", "DBConnectionManager.log");
String logFile = "." + File.separator + "logs" + File.separator + "dbpool";
try {
log = new PrintWriter(new FileWriter(logFile, true), true);
}
catch (IOException e) {
System.err.println("Can′t open the log file: " + logFile);
log = new PrintWriter(System.err);
}
*/
log = new PrintWriter(System.err);
loadDrivers(driver);
createPools(poolName, url, user, passwd, maxconn);
}
/**
* Loads and registers all JDBC drivers. This is done by the
* DBConnectionManager, as opposed to the DBConnectionPool,
* since many pools may share the same driver.
*
* @param props The connection pool properties
*/
private void loadDrivers(String driverClassName) {
/*
String driverClasses = props.getProperty("drivers");
StringTokenizer st = new StringTokenizer(driverClasses);
while (st.hasMoreElements()) {
String driverClassName = st.nextToken().trim();
热心网友
时间：2023-10-15 13:16
配置文件：
hibernate的系统配置类的hibernate.hbm.xml的写法
<?xml version="1.0" encoding="gbk"?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="connection.driver_class">....</property><!--使用的数据库的驱动-->
<property name="connection.url">....</property><!--连接数据库使用的url-->
<property name="connection.username">...</property><!--连接数据库的用户名-->
<property name="connection.password">...</property><!--连接数据库的密码-->
<property name="dialect">....</property><!--使用的数据库方言信息-->
<property name="show_sql">true</property><!--显示sql语句-->
<property name="format_sql">true</property><!--使显示的sql语句格式化-->
<mapping resource="xxx/xxxx/Xxxxxx.hbm.xml"/>
<!--引入的映射对象的xml文件的全路径及文件名-->
</session-factory>
</hibernate-configuration>
java代码
try {
SessionFactory sf = new Configuration().configure().buildSessionFactory();
Session s=sf.openSession();
s.beginTransaction();
//写业务代码
} catch (HibernateException e) {
e.printStackTrace();
s.getTransaction().rollback();
} finally {
s.close();
}
jdbc：
Connection con = null;
Statement st=null;
try {
Class.forName("oracle.jdbc.driver.OracleDriver");
con=DriverManager.getConnection( "jdbc:oracle:thin:@192.168.0.122:1521:oracle","scott","tiger");
String sql="insert into temp_user values("+user.getId()+",'"+user.getName()+"')";
st=con.createStatement();
int num=st.executeUpdate(sql);
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if(st!=null){st.close();}
if(con!=null){con.close();}
} catch (SQLException e) {
e.printStackTrace();
}
}
