1、问题描述：

（1）问题示例：

Step1:创建作业：

[Hadoop@master TestDir]$ sqoop job \
> --create myjob_1 \
> -- import \
> --connect "jdbc:mysql://master:3306/source?useSSL=false&user=Hive&password=******" \
> --table sales_order \
> --columns "order_number,customer_number,product_code,order_date,entry_date,order_amount" \
> --where "entry_date < current_date()" \
> --hive-import \
> --hive-table rds.sales_order \
> --incremental append \
> --check-column entry_date \
> --last-value '1900-01-01'
2021-11-06 15:08:48,003 INFO sqoop.Sqoop: Running Sqoop version: 1.4.7
2021-11-06 15:08:48,242 INFO tool.BaseSqoopTool: Using Hive-specific delimiters for output. You can override
2021-11-06 15:08:48,242 INFO tool.BaseSqoopTool: delimiters with --fields-terminated-by, etc.
Exception in thread "main" java.lang.NoClassDefFoundError: org/json/JSONObject
at org.apache.sqoop.util.SqoopJsonUtil.getJsonStringforMap(SqoopJsonUtil.java:43)
at org.apache.sqoop.SqoopOptions.writeProperties(SqoopOptions.java:785)
at org.apache.sqoop.metastore.hsqldb.HsqldbJobStorage.createInternal(HsqldbJobStorage.java:399)
at org.apache.sqoop.metastore.hsqldb.HsqldbJobStorage.create(HsqldbJobStorage.java:379)
at org.apache.sqoop.tool.JobTool.createJob(JobTool.java:181)
at org.apache.sqoop.tool.JobTool.run(JobTool.java:294)
at org.apache.sqoop.Sqoop.run(Sqoop.java:147)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:76)
at org.apache.sqoop.Sqoop.runSqoop(Sqoop.java:183)
at org.apache.sqoop.Sqoop.runTool(Sqoop.java:234)
at org.apache.sqoop.Sqoop.runTool(Sqoop.java:243)
at org.apache.sqoop.Sqoop.main(Sqoop.java:252)
Caused by: java.lang.ClassNotFoundException: org.json.JSONObject
at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
at java.lang.ClassLoader.loadClass(ClassLoader.java:418)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:355)
at java.lang.ClassLoader.loadClass(ClassLoader.java:351)
... 12 more

Step2:查看作业：
[Hadoop@master TestDir]$ sqoop job --list
2021-11-06 15:09:01,663 INFO sqoop.Sqoop: Running Sqoop version: 1.4.7
Available jobs:
myjob_1

Step3:查看时间戳：
[Hadoop@master TestDir]$ sqoop job --show myjob_1 |grep last.value
2021-11-06 15:09:10,169 INFO sqoop.Sqoop: Running Sqoop version: 1.4.7
Exception in thread "main" java.lang.NoClassDefFoundError: org/json/JSONObject
at org.apache.sqoop.util.SqoopJsonUtil.getJsonStringforMap(SqoopJsonUtil.java:43)
at org.apache.sqoop.SqoopOptions.writeProperties(SqoopOptions.java:785)
at org.apache.sqoop.tool.JobTool.showJob(JobTool.java:261)
at org.apache.sqoop.tool.JobTool.run(JobTool.java:302)
at org.apache.sqoop.Sqoop.run(Sqoop.java:147)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:76)
at org.apache.sqoop.Sqoop.runSqoop(Sqoop.java:183)
at org.apache.sqoop.Sqoop.runTool(Sqoop.java:234)
at org.apache.sqoop.Sqoop.runTool(Sqoop.java:243)
at org.apache.sqoop.Sqoop.main(Sqoop.java:252)
Caused by: java.lang.ClassNotFoundException: org.json.JSONObject
at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
at java.lang.ClassLoader.loadClass(ClassLoader.java:418)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:355)
at java.lang.ClassLoader.loadClass(ClassLoader.java:351)
... 10 more

Step4:提交作业：
[Hadoop@master TestDir]$ sqoop job --exec myjob_1
2021-11-06 15:09:20,062 INFO sqoop.Sqoop: Running Sqoop version: 1.4.7
--table or --query is required for import. (Or use sqoop import-all-tables.)
Try --help for usage instructions.

Step5:二次查看时间戳：
[Hadoop@master TestDir]$ sqoop job --show myjob_1 |grep last.value
2021-11-06 15:09:28,496 INFO sqoop.Sqoop: Running Sqoop version: 1.4.7
Exception in thread "main" java.lang.NoClassDefFoundError: org/json/JSONObject
at org.apache.sqoop.util.SqoopJsonUtil.getJsonStringforMap(SqoopJsonUtil.java:43)
at org.apache.sqoop.SqoopOptions.writeProperties(SqoopOptions.java:785)
at org.apache.sqoop.tool.JobTool.showJob(JobTool.java:261)
at org.apache.sqoop.tool.JobTool.run(JobTool.java:302)
at org.apache.sqoop.Sqoop.run(Sqoop.java:147)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:76)
at org.apache.sqoop.Sqoop.runSqoop(Sqoop.java:183)
at org.apache.sqoop.Sqoop.runTool(Sqoop.java:234)
at org.apache.sqoop.Sqoop.runTool(Sqoop.java:243)
at org.apache.sqoop.Sqoop.main(Sqoop.java:252)
Caused by: java.lang.ClassNotFoundException: org.json.JSONObject
at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
at java.lang.ClassLoader.loadClass(ClassLoader.java:418)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:355)
at java.lang.ClassLoader.loadClass(ClassLoader.java:351)
... 10 more

（2）问题综述：

通过以上步骤示例，Sqoop从MySQL向Hive进行增量式导入数据报错，问题的核心在于：

Exception in thread "main" java.lang.NoClassDefFoundError: org/json/JSONObject

解决该问题，是关键。

2、问题剖析：

（1）参考：https://www.cnblogs.com/QuestionsZhang/p/10082735.html

（2）剖析：根据参考，以及本示例所报出的问题，基本可以肯定是因为Sqoop安装路径下lib目录缺少java-json.jar。因此只需要寻找一个Java-json.jar放入Sqoop安装路径中的lib目录下即可。笔者从最终测试结果可知，此为正解。

3、解决方案：

（1）下载java-json.jar：

下载地址：http://www.java2s.com/Code/JarDownload/java-json/java-json.jar.zip

（2）二次测试：

Step1:创建作业：

[Hadoop@master tmp]$ sqoop job \
> --create myjob_1 \
> -- import \
> --connect "jdbc:mysql://master:3306/source?useSSL=false&user=Hive&password=******" \
> --table sales_order \
> --columns "order_number,customer_number,product_code,order_date,entry_date,order_amount" \
> --where "entry_date < current_date()" \
> --hive-import \
> --hive-table rds.sales_order \
> --incremental append \
> --check-column entry_date \
> --last-value '1900-01-01'
2021-11-06 15:49:52,350 INFO sqoop.Sqoop: Running Sqoop version: 1.4.7
2021-11-06 15:49:52,632 INFO tool.BaseSqoopTool: Using Hive-specific delimiters for output. You can override
2021-11-06 15:49:52,632 INFO tool.BaseSqoopTool: delimiters with --fields-terminated-by, etc.

Step2:查看作业：

[Hadoop@master tmp]$ sqoop job --list
2021-11-06 15:50:10,531 INFO sqoop.Sqoop: Running Sqoop version: 1.4.7
Available jobs:
myjob_1

Step3:查看时间戳：

[Hadoop@master tmp]$ sqoop job --show myjob_1 |grep last.value
2021-11-06 15:50:29,832 INFO sqoop.Sqoop: Running Sqoop version: 1.4.7
incremental.last.value = 1900-01-01

Step4:提交作业：

[Hadoop@master tmp]$ sqoop job --exec myjob_1
2021-11-06 16:05:23,188 INFO sqoop.Sqoop: Running Sqoop version: 1.4.7
2021-11-06 16:05:23,815 INFO manager.MySQLManager: Preparing to use a MySQL streaming resultset.
2021-11-06 16:05:23,851 INFO tool.CodeGenTool: Beginning code generation
Loading class `com.mysql.jdbc.Driver'. This is deprecated. The new driver class is `com.mysql.cj.jdbc.Driver'. The driver is automatically registered via the SPI and manual loading of the driver class is generally unnecessary.
2021-11-06 16:05:27,962 INFO manager.SqlManager: Executing SQL statement: SELECT t.* FROM `sales_order` AS t LIMIT 1
2021-11-06 16:05:29,150 INFO manager.SqlManager: Executing SQL statement: SELECT t.* FROM `sales_order` AS t LIMIT 1
......(此处有省略)
2021-11-06 16:09:35,112 INFO hive.HiveImport: OK
2021-11-06 16:09:35,273 INFO hive.HiveImport: Time taken: 1.611 seconds
2021-11-06 16:09:35,274 INFO hive.HiveImport: 2021-11-06 16:09:35,273 INFO [af634dbf-7808-4849-bd2e-f2b12b7435a8 main] CliDriver (SessionState.java:printInfo(1227)) - Time taken: 1.611 seconds
2021-11-06 16:09:35,274 INFO hive.HiveImport: 2021-11-06 16:09:35,273 INFO [af634dbf-7808-4849-bd2e-f2b12b7435a8 main] conf.HiveConf (HiveConf.java:getLogIdVar(5040)) - Using the default value passed in for log id: af634dbf-7808-4849-bd2e-f2b12b7435a8
2021-11-06 16:09:35,274 INFO hive.HiveImport: 2021-11-06 16:09:35,273 INFO [af634dbf-7808-4849-bd2e-f2b12b7435a8 main] session.SessionState (SessionState.java:resetThreadName(452)) - Resetting thread name to main
2021-11-06 16:09:35,274 INFO hive.HiveImport: 2021-11-06 16:09:35,274 INFO [main] conf.HiveConf (HiveConf.java:getLogIdVar(5040)) - Using the default value passed in for log id: af634dbf-7808-4849-bd2e-f2b12b7435a8
2021-11-06 16:09:35,319 INFO hive.HiveImport: 2021-11-06 16:09:35,318 INFO [main] session.SessionState (SessionState.java:dropPathAndUnregisterDeleteOnExit(885)) - Deleted directory: /user/hive/tmp/grid/af634dbf-7808-4849-bd2e-f2b12b7435a8 on fs with scheme hdfs
2021-11-06 16:09:35,319 INFO hive.HiveImport: 2021-11-06 16:09:35,319 INFO [main] session.SessionState (SessionState.java:dropPathAndUnregisterDeleteOnExit(885)) - Deleted directory: /tmp/hive/Local/af634dbf-7808-4849-bd2e-f2b12b7435a8 on fs with scheme file
2021-11-06 16:09:35,319 INFO hive.HiveImport: 2021-11-06 16:09:35,319 INFO [main] metastore.HiveMetaStoreClient (HiveMetaStoreClient.java:close(600)) - Closed a connection to metastore, current connections: 1
2021-11-06 16:09:35,389 INFO hive.HiveImport: Hive import complete.
2021-11-06 16:09:35,392 INFO hive.HiveImport: Export directory is empty, removing it.
2021-11-06 16:09:35,408 INFO tool.ImportTool: Saving incremental import state to the metastore
2021-11-06 16:09:35,454 INFO tool.ImportTool: Updated data for job: myjob_1

Step5:二次查看时间戳：

[Hadoop@master tmp]$ sqoop job --show myjob_1 |grep last.value
2021-11-06 16:09:45,037 INFO sqoop.Sqoop: Running Sqoop version: 1.4.7
incremental.last.value = 2016-06-30 17:26:24.0

二次查看时间戳的目的是验证：Sqoop是不是成功将MySQL中数据采用增量式导入Hive中，此外还可以在Hive查看数据进行验证。