我正在尝试在Pentaho 5.3.0.0-213中建立到localhost上mysql的连接。我使用的是运行OS 10.10.2的Mac。我可以使用Sequel Pro连接到数据库，并且已经阅读了这个网站（以及其他网站！）上已经给出的所有答案，并且已经下载并复制了mysql-connector-java-5.1.34bin.jar到data integration/lib，但仍然会得到相同的错误。
欢迎提出任何建议。
整个错误消息如下：连接到数据库[localhost_con]时出错：org.pentaho.di.core.exception.KettleDatabaseException：尝试连接到数据库时出错
连接到数据库时出错：（使用org.gjit.mm.mysql.Driver类）通信链路故障
最后一个成功发送到服务器的数据包是0毫秒前。驱动程序尚未从服务器接收到任何数据包。
org.pentaho.di.core.exception.KettleDatabaseException：尝试连接到数据库时出错
连接到数据库时出错：（使用org.gjit.mm.mysql.Driver类）通信链路故障
最后一个成功发送到服务器的数据包是0毫秒前。驱动程序尚未从服务器接收到任何数据包。
at org.pentaho.di.core.database.Database.normalConnect(Database.java:417)
at org.pentaho.di.core.database.Database.connect(Database.java:357)
at org.pentaho.di.core.database.Database.connect(Database.java:310)
at org.pentaho.di.core.database.Database.connect(Database.java:300)
at org.pentaho.di.core.database.DatabaseFactory.getConnectionTestReport(DatabaseFactory.java:80)
at org.pentaho.di.core.database.DatabaseMeta.testConnection(DatabaseMeta.java:2685)
at org.pentaho.ui.database.event.DataHandler.testDatabaseConnection(DataHandler.java:546)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.pentaho.ui.xul.impl.AbstractXulDomContainer.invoke(AbstractXulDomContainer.java:313)
at org.pentaho.ui.xul.impl.AbstractXulComponent.invoke(AbstractXulComponent.java:157)
at org.pentaho.ui.xul.impl.AbstractXulComponent.invoke(AbstractXulComponent.java:141)
at org.pentaho.ui.xul.swt.tags.SwtButton.access$500(SwtButton.java:43)
at org.pentaho.ui.xul.swt.tags.SwtButton$4.widgetSelected(SwtButton.java:138)
at org.eclipse.swt.widgets.TypedListener.handleEvent(Unknown Source)
at org.eclipse.swt.widgets.EventTable.sendEvent(Unknown Source)
at org.eclipse.swt.widgets.Display.sendEvent(Unknown Source)
at org.eclipse.swt.widgets.Widget.sendEvent(Unknown Source)
at org.eclipse.swt.widgets.Widget.sendEvent(Unknown Source)
at org.eclipse.swt.widgets.Widget.sendEvent(Unknown Source)
at org.eclipse.swt.widgets.Widget.notifyListeners(Unknown Source)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Unknown Source)
at org.eclipse.swt.widgets.Display.readAndDispatch(Unknown Source)
at org.eclipse.jface.window.Window.runEventLoop(Window.java:820)
at org.eclipse.jface.window.Window.open(Window.java:796)
at org.pentaho.ui.xul.swt.tags.SwtDialog.show(SwtDialog.java:389)
at org.pentaho.ui.xul.swt.tags.SwtDialog.show(SwtDialog.java:318)
at org.pentaho.di.ui.core.database.dialog.XulDatabaseDialog.open(XulDatabaseDialog.java:116)
at org.pentaho.di.ui.core.database.dialog.DatabaseDialog.open(DatabaseDialog.java:59)
at org.pentaho.di.ui.spoon.delegates.SpoonDBDelegate.editConnection(SpoonDBDelegate.java:87)
at org.pentaho.di.ui.spoon.Spoon.doubleClickedInTree(Spoon.java:3096)
at org.pentaho.di.ui.spoon.Spoon.doubleClickedInTree(Spoon.java:3031)
at org.pentaho.di.ui.spoon.Spoon.access$2400(Spoon.java:347)
at org.pentaho.di.ui.spoon.Spoon$27.widgetDefaultSelected(Spoon.java:6121)
at org.eclipse.swt.widgets.TypedListener.handleEvent(Unknown Source)
at org.eclipse.swt.widgets.EventTable.sendEvent(Unknown Source)
at org.eclipse.swt.widgets.Display.sendEvent(Unknown Source)
at org.eclipse.swt.widgets.Widget.sendEvent(Unknown Source)
at org.eclipse.swt.widgets.Widget.sendEvent(Unknown Source)
at org.eclipse.swt.widgets.Widget.sendEvent(Unknown Source)
at org.eclipse.swt.widgets.Widget.notifyListeners(Unknown Source)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Unknown Source)
at org.eclipse.swt.widgets.Display.readAndDispatch(Unknown Source)
at org.pentaho.di.ui.spoon.Spoon.readAndDispatch(Spoon.java:1316)
at org.pentaho.di.ui.spoon.Spoon.waitForDispose(Spoon.java:7979)
at org.pentaho.di.ui.spoon.Spoon.start(Spoon.java:9310)
at org.pentaho.di.ui.spoon.Spoon.main(Spoon.java:654)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.pentaho.commons.launcher.Launcher.main(Launcher.java:92)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at apple.launcher.LaunchRunner.run(LaunchRunner.java:116)
at apple.launcher.LaunchRunner.callMain(LaunchRunner.java:51)
at apple.launcher.JavaApplicationLauncher.launch(JavaApplicationLauncher.java:52)
Caused by: org.pentaho.di.core.exception.KettleDatabaseException:
Error connecting to database: (using class org.gjt.mm.mysql.Driver)
Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
at org.pentaho.di.core.database.Database.connectUsingClass(Database.java:561)
at org.pentaho.di.core.database.Database.normalConnect(Database.java:400)
... 60 more
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:377)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1036)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:338)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2232)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2265)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2064)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:790)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:44)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:377)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:395)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:325)
at java.sql.DriverManager.getConnection(DriverManager.java:582)
at java.sql.DriverManager.getConnection(DriverManager.java:185)
at org.pentaho.di.core.database.Database.connectUsingClass(Database.java:543)
... 61 more
Caused by: java.net.ConnectException: Connection refused
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:382)
at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:241)
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:228)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:431)
at java.net.Socket.connect(Socket.java:527)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:213)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:297)
... 76 more
主机名：localhost端口：3306数据库名称：my_learning_sql
我看到这个问题取决于数据库的版本和MySQL驱动程序的版本。我使用的是mysql-connector-java-5.1.17.jar，为了让我的工作正常进行，我不得不升级到mysql-connector-java-5.1.34-bin.jar。也许您的问题正好相反，您可以将驱动程序降级为mysql-connector-java-5.1.17.jar来修复您的问题？
我遇到了类似的问题（与您上面列出的驱动程序、操作系统等的版本相同），最终追踪到：我的~/.kettle/kettle.properties文件没有像转换中的数据库连接那样列出DB主机设置。
deweygarwood$ cat ~/.kettle/kettle.properties
# This file was generated by Pentaho Data Integration version 5.1.2.1.
... stuff here
DW_HOST=localhost <~~~ this line
DW_DBPORT=3306
DW_DBNAME=datawarehouse
DW_DBUSER=root
DW_DBPASSWORD=
与水壶转换中我的数据库连接中列出的名称不匹配，该名称为${DW_DBHOST}
我发现这一点的方式是使用数据库连接屏幕上的"测试"按钮并滚动到底部。输出显示的是变量"$｛DW_DBHOST｝"，而不是"localhost"。更新我的~/.kettle/kettle.properties文件以使用相同的变量名解决了问题。
假设您正在使用kettle.properties进行连接设置，我预计会出现类似的情况。
- 从这里下载Mysql连接器：连接器
- 解压缩文件
- 只将两个*.jar文件复制到dataintegration/lib中/
- 重启Pentaho
- 转到：数据库连接->选择MySql->编辑连接信息->测试连接
这些步骤解决了我的问题。