package cn.liz.test;import java.io.InputStream;import java.sql.Connection;import java.sql.Driver;import java.sql.SQLException;import java.util.Properties;import org.junit.Test;public class JBDCtest { /** * 编写一个通用的方法, 在不修改源程序的情况下, 可以获取任何数据库的连接 * 解决方案: 把数据库驱动 Driver 实现类的全类名、url、user、password 放入一个 * 配置文件中, 通过修改配置文件的方式实现和具体的数据库解耦. * @throws Exception */ public Connection getConnection() throws Exception{ String driverClass = null; String jdbcUrl = null; String user = null; String password = null; //读取类路径下的 jdbc.properties 文件 InputStream in = getClass().getClassLoader().getResourceAsStream("jdbc.properties"); Properties properties = new Properties(); properties.load(in); driverClass = properties.getProperty("driver"); jdbcUrl = properties.getProperty("jdbcUrl"); user = properties.getProperty("user"); password = properties.getProperty("password"); //通过反射常见 Driver 对象. Driver driver = (Driver) Class.forName(driverClass).newInstance(); Properties info = new Properties(); info.put("user", user); info.put("password", password); //通过 Driver 的 connect 方法获取数据库连接. Connection connection = driver.connect(jdbcUrl, info); return connection; } @Test public void testGetConnection() throws Exception{ System.out.println(getConnection()); }}<span style="white-space:pre"> </span>
<span style="font-family: Arial, Helvetica, sans-serif;">jdbc.properties</span>配置文件:
#driver=oracle.jdbc.driver.OracleDriver#jdbcUrl=jdbc:oracle:thin:@localhost:1521:orcl#user=scott#password=javadriver=com.mysql.jdbc.DriverjdbcUrl=jdbc:mysql://localhost:3306/testuser=rootpassword=

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MySQL backup policies include logical backup, physical backup, incremental backup, replication-based backup, and cloud backup. 1. Logical backup uses mysqldump to export database structure and data, which is suitable for small databases and version migrations. 2. Physical backups are fast and comprehensive by copying data files, but require database consistency. 3. Incremental backup uses binary logging to record changes, which is suitable for large databases. 4. Replication-based backup reduces the impact on the production system by backing up from the server. 5. Cloud backups such as AmazonRDS provide automation solutions, but costs and control need to be considered. When selecting a policy, database size, downtime tolerance, recovery time, and recovery point goals should be considered.

MySQLclusteringenhancesdatabaserobustnessandscalabilitybydistributingdataacrossmultiplenodes.ItusestheNDBenginefordatareplicationandfaulttolerance,ensuringhighavailability.Setupinvolvesconfiguringmanagement,data,andSQLnodes,withcarefulmonitoringandpe

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