java连接器与MySql版本对应问题
java连接器
发布日期:   2019-12-11

两种版本的MySQL Connector / J

  • Connector / J 5.1是Type 4纯Java JDBC驱动程序，符合JDBC 3.0、4.0、4.1和4.2规范。 它与MySQL的所有功能（包括5.6、5.7和8.0）兼容。 Connector / J 5.1提供了易于开发的功能，包括使用驱动程序管理器自动注册，标准化的有效性检查，分类的SQLException，对大量更新计数的支持，对java.time包中本地和偏移日期时间变体的支持，对JDBC-4.x XML处理，支持每个连接客户端信息，并支持NCHAR ， NVARCHAR和NCLOB数据类型。
  • Connector / J 8.0是用于Java 8平台的Type 4纯Java JDBC 4.2驱动程序。 它提供与MySQL 5.6、5.7和8.0的所有功能的兼容性。 有关详细信息，请参见《 MySQL Connector / J 8.0开发人员指南 》。

下表总结了可用的Connector / J版本，以及不同版本的JDBC，MySQL Server和Java的兼容性信息，以及每种Connector / J版本的支持状态：

表2.1 Connector / J 版本摘要

问题：在跟随着 Kubernetes权威指南 第4版.pdf 学习过程中，1.3节中的一个 java 的demo实例中，通过yaml创建了Web App容器和MySQL容器，Web App容器需要访问MySQL容器。下面我把这两个服务的yaml文件pose出来：

mysql的deployment和service的yaml文件

apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: mysql
  labels:
    app: mysql
spec:
  replicas: 1
  selector:
    matchLabels:
      app: mysql
  template:
    metadata:
      labels:
        app: mysql
    spec:
      containers:
      - name: mysql
        image: mysql
        ports:
        - containerPort: 3306
        env:
        - name: MYSQL_ROOT_PASSWORD
          value: "123456"
---
apiVersion: v1
kind: Service
metadata:
  name: mysql
spec:
  ports:
    - port: 3306
  selector:
    app: mysql

Web APP的deployment和service的yaml文件：

apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: myweb
spec:
  replicas: 2
  selector:
    matchLabels:
     app: myweb
  template:
    metadata:
      labels:
        app: myweb
    spec:
      containers:
        - name: myweb
          image: kubeguide/tomcat-app:v1
          ports:
          - containerPort: 8080
---
apiVersion: v1
kind: Service
metadata:
  name: myweb
spec:
  type: NodePort
  ports:
    - port: 8080
  selector:
    app: myweb

但是在kubectl create -f 这两个文件后，查看其中的一个 Pod 日志发现报错信息：

[root@k8s-master test]# kubectl logs myweb-6557d8b869-xk9m9
11-Dec-2019 06:05:00.070 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Server version:        Apache Tomcat/8.0.35
11-Dec-2019 06:05:00.071 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Server built:          May 11 2016 21:57:08 UTC
11-Dec-2019 06:05:00.071 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Server number:         8.0.35.0
11-Dec-2019 06:05:00.072 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log OS Name:               Linux
11-Dec-2019 06:05:00.072 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log OS Version:            3.10.0-1062.4.1.el7.x86_64
11-Dec-2019 06:05:00.072 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Architecture:          amd64
11-Dec-2019 06:05:00.072 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Java Home:             /usr/lib/jvm/java-7-openjdk-amd64/jre
11-Dec-2019 06:05:00.072 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log JVM Version:           1.7.0_101-b00
11-Dec-2019 06:05:00.072 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log JVM Vendor:            Oracle Corporation
11-Dec-2019 06:05:00.072 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log CATALINA_BASE:         /usr/local/tomcat
11-Dec-2019 06:05:00.073 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log CATALINA_HOME:         /usr/local/tomcat
11-Dec-2019 06:05:00.073 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.util.logging.config.file=/usr/local/tomcat/conf/logging.properties
11-Dec-2019 06:05:00.073 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager
11-Dec-2019 06:05:00.073 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djdk.tls.ephemeralDHKeySize=2048
11-Dec-2019 06:05:00.073 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.endorsed.dirs=/usr/local/tomcat/endorsed
11-Dec-2019 06:05:00.073 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcatalina.base=/usr/local/tomcat
11-Dec-2019 06:05:00.073 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcatalina.home=/usr/local/tomcat
11-Dec-2019 06:05:00.074 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.io.tmpdir=/usr/local/tomcat/temp
11-Dec-2019 06:05:00.074 INFO [main] org.apache.catalina.core.AprLifecycleListener.lifecycleEvent Loaded APR based Apache Tomcat Native library 1.2.7 using APR version 1.5.1.
11-Dec-2019 06:05:00.074 INFO [main] org.apache.catalina.core.AprLifecycleListener.lifecycleEvent APR capabilities: IPv6 [true], sendfile [true], accept filters [false], random [true].
11-Dec-2019 06:05:00.078 INFO [main] org.apache.catalina.core.AprLifecycleListener.initializeSSL OpenSSL successfully initialized (OpenSSL 1.0.2h  3 May 2016)
11-Dec-2019 06:05:00.179 INFO [main] org.apache.coyote.AbstractProtocol.init Initializing ProtocolHandler ["http-apr-8080"]
11-Dec-2019 06:05:00.192 INFO [main] org.apache.coyote.AbstractProtocol.init Initializing ProtocolHandler ["ajp-apr-8009"]
11-Dec-2019 06:05:00.195 INFO [main] org.apache.catalina.startup.Catalina.load Initialization processed in 575 ms
11-Dec-2019 06:05:00.222 INFO [main] org.apache.catalina.core.StandardService.startInternal Starting service Catalina
11-Dec-2019 06:05:00.222 INFO [main] org.apache.catalina.core.StandardEngine.startInternal Starting Servlet Engine: Apache Tomcat/8.0.35
11-Dec-2019 06:05:00.231 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory /usr/local/tomcat/webapps/ROOT
11-Dec-2019 06:05:00.563 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory /usr/local/tomcat/webapps/ROOT has finished in 332 ms
11-Dec-2019 06:05:00.563 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory /usr/local/tomcat/webapps/docs
11-Dec-2019 06:05:00.586 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory /usr/local/tomcat/webapps/docs has finished in 23 ms
11-Dec-2019 06:05:00.586 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory /usr/local/tomcat/webapps/examples
11-Dec-2019 06:05:00.915 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory /usr/local/tomcat/webapps/examples has finished in 329 ms
11-Dec-2019 06:05:00.915 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory /usr/local/tomcat/webapps/host-manager
11-Dec-2019 06:05:00.956 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory /usr/local/tomcat/webapps/host-manager has finished in 41 ms
11-Dec-2019 06:05:00.957 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory /usr/local/tomcat/webapps/manager
11-Dec-2019 06:05:00.979 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory /usr/local/tomcat/webapps/manager has finished in 23 ms
11-Dec-2019 06:05:00.980 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory /usr/local/tomcat/webapps/demo
11-Dec-2019 06:05:01.134 INFO [localhost-startStop-1] org.apache.jasper.servlet.TldScanner.scanJars At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.
11-Dec-2019 06:05:01.139 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory /usr/local/tomcat/webapps/demo has finished in 159 ms
11-Dec-2019 06:05:01.143 INFO [main] org.apache.coyote.AbstractProtocol.start Starting ProtocolHandler ["http-apr-8080"]
11-Dec-2019 06:05:01.155 INFO [main] org.apache.coyote.AbstractProtocol.start Starting ProtocolHandler ["ajp-apr-8009"]
11-Dec-2019 06:05:01.156 INFO [main] org.apache.catalina.startup.Catalina.start Server startup in 961 ms
Connecting to database...
com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server.
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:404)
    at com.mysql.jdbc.Util.getInstance(Util.java:387)
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:919)
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:898)
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:887)
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:862)
    at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2331)
    at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2084)
    at com.mysql.jdbc.ConnectionImpl.(ConnectionImpl.java:795)
    at com.mysql.jdbc.JDBC4Connection.(JDBC4Connection.java:44)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:404)
    at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:400)
    at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:327)
    at java.sql.DriverManager.getConnection(DriverManager.java:571)
    at java.sql.DriverManager.getConnection(DriverManager.java:215)
    at org.apache.jsp.index_jsp._jspService(index_jsp.java:133)
    at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
    at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:438)
    at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:396)
    at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:340)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:292)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:212)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:141)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
    at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:528)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1099)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:672)
    at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.doRun(AprEndpoint.java:2508)
    at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:2497)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.NullPointerException
    at com.mysql.jdbc.ConnectionImpl.getServerCharset(ConnectionImpl.java:3004)
    at com.mysql.jdbc.MysqlIO.sendConnectionAttributes(MysqlIO.java:1908)
    at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1837)
    at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1207)
    at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2254)
    at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2285)
    ... 40 more
Goodbye!

查看了Web APP 的pod项目程序里面用的连接器是mysql-connector-java-5.1.37.jar，java环境是JAVA_HOME=/usr/lib/jvm/java-7-openjdk-amd64/jre，后端的数据库是 mysql Ver 8.0.18 for Linux on x86_64 (MySQL Community Server - GPL)，由于后端数据库为社区版8.0.18，最新版的，连接器不支持。造成连接不上数据库，我们把mysql的yaml中 image: mysql 修改为： image: mysql:5.7 或者 mysql:5.6

[root@k8s-master test]# kubectl logs myweb-6557d8b869-c9t5z
11-Dec-2019 06:31:54.876 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Server version:        Apache Tomcat/8.0.35
11-Dec-2019 06:31:54.877 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Server built:          May 11 2016 21:57:08 UTC
11-Dec-2019 06:31:54.877 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Server number:         8.0.35.0
11-Dec-2019 06:31:54.877 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log OS Name:               Linux
11-Dec-2019 06:31:54.877 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log OS Version:            3.10.0-862.el7.x86_64
11-Dec-2019 06:31:54.877 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Architecture:          amd64
11-Dec-2019 06:31:54.877 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Java Home:             /usr/lib/jvm/java-7-openjdk-amd64/jre
11-Dec-2019 06:31:54.878 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log JVM Version:           1.7.0_101-b00
11-Dec-2019 06:31:54.878 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log JVM Vendor:            Oracle Corporation
11-Dec-2019 06:31:54.878 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log CATALINA_BASE:         /usr/local/tomcat
11-Dec-2019 06:31:54.878 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log CATALINA_HOME:         /usr/local/tomcat
11-Dec-2019 06:31:54.878 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.util.logging.config.file=/usr/local/tomcat/conf/logging.properties
11-Dec-2019 06:31:54.878 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager
11-Dec-2019 06:31:54.878 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djdk.tls.ephemeralDHKeySize=2048
11-Dec-2019 06:31:54.878 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.endorsed.dirs=/usr/local/tomcat/endorsed
11-Dec-2019 06:31:54.878 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcatalina.base=/usr/local/tomcat
11-Dec-2019 06:31:54.879 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcatalina.home=/usr/local/tomcat
11-Dec-2019 06:31:54.879 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.io.tmpdir=/usr/local/tomcat/temp
11-Dec-2019 06:31:54.879 INFO [main] org.apache.catalina.core.AprLifecycleListener.lifecycleEvent Loaded APR based Apache Tomcat Native library 1.2.7 using APR version 1.5.1.
11-Dec-2019 06:31:54.879 INFO [main] org.apache.catalina.core.AprLifecycleListener.lifecycleEvent APR capabilities: IPv6 [true], sendfile [true], accept filters [false], random [true].
11-Dec-2019 06:31:54.882 INFO [main] org.apache.catalina.core.AprLifecycleListener.initializeSSL OpenSSL successfully initialized (OpenSSL 1.0.2h  3 May 2016)
11-Dec-2019 06:31:54.971 INFO [main] org.apache.coyote.AbstractProtocol.init Initializing ProtocolHandler ["http-apr-8080"]
11-Dec-2019 06:31:54.981 INFO [main] org.apache.coyote.AbstractProtocol.init Initializing ProtocolHandler ["ajp-apr-8009"]
11-Dec-2019 06:31:54.983 INFO [main] org.apache.catalina.startup.Catalina.load Initialization processed in 507 ms
11-Dec-2019 06:31:55.008 INFO [main] org.apache.catalina.core.StandardService.startInternal Starting service Catalina
11-Dec-2019 06:31:55.008 INFO [main] org.apache.catalina.core.StandardEngine.startInternal Starting Servlet Engine: Apache Tomcat/8.0.35
11-Dec-2019 06:31:55.018 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory /usr/local/tomcat/webapps/ROOT
11-Dec-2019 06:31:55.329 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory /usr/local/tomcat/webapps/ROOT has finished in 311 ms
11-Dec-2019 06:31:55.329 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory /usr/local/tomcat/webapps/docs
11-Dec-2019 06:31:55.349 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory /usr/local/tomcat/webapps/docs has finished in 19 ms
11-Dec-2019 06:31:55.349 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory /usr/local/tomcat/webapps/examples
11-Dec-2019 06:31:55.635 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory /usr/local/tomcat/webapps/examples has finished in 286 ms
11-Dec-2019 06:31:55.635 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory /usr/local/tomcat/webapps/host-manager
11-Dec-2019 06:31:55.659 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory /usr/local/tomcat/webapps/host-manager has finished in 24 ms
11-Dec-2019 06:31:55.659 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory /usr/local/tomcat/webapps/manager
11-Dec-2019 06:31:55.679 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory /usr/local/tomcat/webapps/manager has finished in 20 ms
11-Dec-2019 06:31:55.680 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory /usr/local/tomcat/webapps/demo
11-Dec-2019 06:31:55.818 INFO [localhost-startStop-1] org.apache.jasper.servlet.TldScanner.scanJars At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.
11-Dec-2019 06:31:55.823 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory /usr/local/tomcat/webapps/demo has finished in 143 ms
11-Dec-2019 06:31:55.828 INFO [main] org.apache.coyote.AbstractProtocol.start Starting ProtocolHandler ["http-apr-8080"]
11-Dec-2019 06:31:55.838 INFO [main] org.apache.coyote.AbstractProtocol.start Starting ProtocolHandler ["ajp-apr-8009"]
11-Dec-2019 06:31:55.844 INFO [main] org.apache.catalina.startup.Catalina.start Server startup in 860 ms
Connecting to database...
Database created successfully...
table created successfully...
demo records inserted successfully...
find record
find record
find record
find record
find record
find record
Goodbye!
Connecting to database...
Goodbye!
Connecting to database...
find record
find record
find record
find record
find record
find record
find record
Goodbye!
文章作者: 阿培
版权声明: 本博客所有文章除特別声明外，均采用 CC BY 4.0 许可协议。转载请注明来源 阿培 !
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