mysql在数据库中创建表 2．ICX可以同时连接多台数据库（2-16台，具体连多少台，看客户的具体需求而定），这若干台数据库的内容在任何时刻由ICX保证是完全一致的
系统可通过短信、邮件、动画等多种告警手段来保证告警的实时性
一般来说，所有年份的数据都在同一个表中
同时请记住，本文并未囊括所有的ORACLE数据导入技术（比如并行数据导入技术），这需要我们继续不懈的探索和尝试
JDBCPoolAppender代码和其相关代码如下：JDBCPoolAppender.java:package common.log;import java.sql.Connection;import org.apache.log4j.spi.LoggingEvent;import java.sql.SQLException;import java.sql.Statement;import java.util.Iterator;import org.apache.log4j.spi.ErrorCode;import org.apache.log4j.PatternLayout;import common.sql.MyDB;import common.sql.GeneralDb;public class JDBCPoolAppender extends org.apache.log4j.jdbc.JDBCAppender {private MyDB mydb = null;protected String sqlname=""""; //增加一个数据库jndiName的属性protected Connection connection = null;protected String sqlStatement = """";/*** size of LoggingEvent buffer before writting to the database.* Default is 1.*/protected int bufferSize = 1;public JDBCPoolAppender() {super();}/*** ArrayList holding the buffer of Logging Events.*/public void append(LoggingEvent event) {buffer.add(event);if (buffer.size() >= bufferSize)flushBuffer();}/*** By default getLogStatement sends the event to the required Layout object.* The layout will format the given pattern into a workable SQL string.** Overriding this provides direct access to the LoggingEvent* when constructing the logging statement.**/protected String getLogStatement(LoggingEvent event) {return getLayout().format(event);}/**** Override this to provide an alertnate method of getting* connections (such as caching). One method to fix this is to open* connections at the start of flushBuffer() and close them at the* end. I use a connection pool outside of JDBCAppender which is* accessed in an override of this method.* */protected void execute(String sql) throws SQLException {Connection con = null;Statement stmt = null;try {con = getConnection();stmt = con.createStatement();stmt.executeUpdate(sql);} catch (SQLException e) {if (stmt != null)stmt.close();throw e;}stmt.close();closeConnection(con);//System.out.println(""Execute: "" + sql);}/*** Override this to return the connection to a pool, or to clean up the* resource.** The default behavior holds a single connection open until the appender* is closed (typically when garbage collected).*/protected void closeConnection(Connection con) {mydb=null;try {if (connection != null && !connection.isClosed())connection.close();} catch (SQLException e) {errorHandler.error(""Error closing connection"", e,ErrorCode.GENERIC_FAILURE);}}/*** Override 此函数来利用连接池返回一个Connetion对象**/protected Connection getConnection() throws SQLException {try {mydb = GeneralDb.getInstance(sqlname);connection = mydb.getConnection();} catch (Exception e) {errorHandler.error(""Error opening connection"", e, ErrorCode.GENERIC_FAILURE);}return connection;}/*** Closes the appender, flushing the buffer first then closing the default* connection if it is open.*/public void close() {flushBuffer();try {if (connection != null && !connection.isClosed())connection.close();} catch (SQLException e) {errorHandler.error(""Error closing connection"", e,ErrorCode.GENERIC_FAILURE);}this.closed = true;}/*** loops through the buffer of LoggingEvents, gets a* sql string from getLogStatement() and sends it to execute().* Errors are sent to the errorHandler.** If a statement fails the LoggingEvent stays in the buffer!*/public void flushBuffer() {//Do the actual loggingremoves.ensureCapacity(buffer.size());for (Iterator i = buffer.iterator(); i.hasNext(); ) {try {LoggingEvent logEvent = (LoggingEvent) i.next();String sql = getLogStatement(logEvent);execute(sql);removes.add(logEvent);} catch (SQLException e) {errorHandler.error(""Failed to excute sql"", e,ErrorCode.FLUSH_FAILURE);}}// remove from the buffer any events that were reportedbuffer.removeAll(removes);// clear the buffer of reported eventsremoves.clear();}/** closes the appender before disposal */public void finalize() {close();}/*** JDBCAppender requires a layout.* */public boolean requiresLayout() {return true;}/****/public void setSql(String s) {sqlStatement = s;if (getLayout() == null) {this.setLayout(new PatternLayout(s));} else {((PatternLayout) getLayout()).setConversionPattern(s);}}/*** Returns pre-formated statement eg: insert into LogTable (msg) values (""%m"")*/public String getSql() {return sqlStatement;}public void setSqlname(String sqlname){sqlname=sqlname;}public String getSqlname(){return sqlname;}public void setBufferSize(int newBufferSize) {bufferSize = newBufferSize;buffer.ensureCapacity(bufferSize);removes.ensureCapacity(bufferSize);}public int getBufferSize() {return bufferSize;}}MyDB.java:package common.sql;import java.sql.*;import com.codestudio.sql.*; //引入开源项目Poolman数据库连接池的包public class MyDB {public static final String module = MyDB.class.getName();private String dbName = """";private PoolMan plmn = null;public MyDB(String dbName) {try {if (plmn == null) {plmn = (PoolMan) Class.forName(""com.codestudio.sql.PoolMan"").newInstance();}} catch (Exception ec) {System.out.println(ec.toString()+module);}this.dbName = dbName;}private Connection getNewConnection() {Connection conn = null;try {conn = plmn.connect(""jdbc:poolman://"" + dbName);conn.setAutoCommit(true);} catch (Exception ec) {System.out.println(ec.toString()+""First:Connect sqlsever failed""+module);try {Thread.sleep(1000);conn = plmn.connect(""jdbc:poolman://"" + dbName);conn.setAutoCommit(true);} catch (Exception ecs) {System.out.println(ecs.toString()+""Again:Connect sqlsever faile""+module);}}return conn;}public Connection getConnection() {return getNewConnection();}}GeneralDb.java:package common.sql;package common.sql;import java.util.*;public class GeneralDb {private static Hashtable dbPool;public static MyDB getInstance(String dbname) {if (dbPool == null) {dbPool = new Hashtable();}MyDB db = (MyDB) dbPool.get(dbname);if (db == null) {db = new MyDB(dbname);dbPool.put(dbname, db);}return db;}}Log4j数据库连接池的配置如下：log4j.appender.JDBC=common.log.JDBCPoolAppenderlog4j.appender.JDBC.sqlname=loglog4j.appender.JDBC.layout=org.apache.log4j.PatternLayoutlog4j.appender.JDBC.sql=INSERT INTO LOGGING (log_date, log_level, location, message) VALUES ('%d{ISO8601}', '%-5p', '%C,%L', '%m')poolman.xml配置如下：localloglogcom.mysql.jdbc.Driverjdbc:mysql://localhost:3306/testusepassword010logs/mysql.log?运行成功！对于JDBCPoolAppender的属性（比如sqlname属性）我们可以利用Log4j的反射机制随便添加，只要在配置文件给其附上值即可应用，而原来的父类里面的一些属性（username什么的)和其get,set方法由于在连接池中不需要，所以删除
目前MySQL DBA行业发展特点：行业内的从业者越来越多了，平均或总体技术水平 越来越低;能用MySQL思想，做事情的合格DBA人数并未大量增加;随着年龄增长，早期80%以上DBA都退出一线了;市场占有率越来越高，高技能或综合素质高的DBA人数却逐年减少趋势;唯一值得庆幸趋势是研究源码的人越来越多，研究源码的能力也越来越强
如果遇到了CBO优化器真的无法做出正确判断，非要使用错误的执行计划的时候，开发人员还是可以通过HINT来强制矫正执行计划的
新的列式功能使用户能够在Xpand中运行特别的查询，速度可提高50倍
总之从底层到上层设计，各个组件之间的交互充分考虑到并行能力
当提及软件的性能，SQL服务器的稳定性要比它的竞争对手强很多
有关游标功能的更多信息，请参见数据访问技术
所有的软件更新和所有 Updates Publisher 设置都将进行备份而且很容易进行还原
该手机所搭载的处理器主频为2.2GHz，共有八个核心，配备Adreno 510 GPU，这与传闻中的高通骁龙660的参数基本一致
好视通与华为邂逅2014Postgres中国大会12月12-13日，2014年Postgres中国用户大会在深圳南山盛大召开，来自全国近300名信息产业的技术精英、科研专家齐聚一堂，针对Postgres的管理培训、新处理技术、应用案例与运维、程序开发等几大议题进行了深度剖析与交流
目前主要研究数据安全、敏捷运维等方向
当前具有一定规模的设计院都已具备网络平台，并且应用了部分专业应用系统;基于现有分散业务系统整合并构建企业综合业务系统平台的需求也是非常迫切
另外，Exchange 2003做的一些基础改进，也使得增加存储组更可靠
2017年9月，大赛即将再度启程，以全新升级的面貌迎接更多充满智慧与创意的参赛团队，掀起新一轮中国青年科普热潮
我们知道在Windows下VB、PB、Delphi等工具提供了一个功能很强的树型控件TreeView，利用Treeview控件可以方便地开发树形图
