我在Mac上使用docker image sequenceiq / spark研究了这些spark示例,在学习过程中,根据此答案,将映像中的spark升级到1.6.1 ,并且在启动Simple Data Operations示例时发生了错误,这是什么发生了:
Simple Data Operations
当我运行df = sqlContext.read.format("jdbc").option("url",url).option("dbtable","people").load()它会引发一个错误,而pyspark控制台的完整堆栈如下所示:
df = sqlContext.read.format("jdbc").option("url",url).option("dbtable","people").load()
Python 2.6.6 (r266:84292, Jul 23 2015, 15:22:56) [GCC 4.4.7 20120313 (Red Hat 4.4.7-11)] on linux2 Type "help", "copyright", "credits" or "license" for more information. 16/04/12 22:45:28 WARN NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable Welcome to ____ __ / __/__ ___ _____/ /__ _\ \/ _ \/ _ `/ __/ '_/ /__ / .__/\_,_/_/ /_/\_\ version 1.6.1 /_/ Using Python version 2.6.6 (r266:84292, Jul 23 2015 15:22:56) SparkContext available as sc, HiveContext available as sqlContext. >>> url = "jdbc:mysql://localhost:3306/test?user=root;password=myPassWord" >>> df = sqlContext.read.format("jdbc").option("url",url).option("dbtable","people").load() 16/04/12 22:46:05 WARN Connection: BoneCP specified but not present in CLASSPATH (or one of dependencies) 16/04/12 22:46:06 WARN Connection: BoneCP specified but not present in CLASSPATH (or one of dependencies) 16/04/12 22:46:11 WARN ObjectStore: Version information not found in metastore. hive.metastore.schema.verification is not enabled so recording the schema version 1.2.0 16/04/12 22:46:11 WARN ObjectStore: Failed to get database default, returning NoSuchObjectException 16/04/12 22:46:16 WARN Connection: BoneCP specified but not present in CLASSPATH (or one of dependencies) 16/04/12 22:46:17 WARN Connection: BoneCP specified but not present in CLASSPATH (or one of dependencies) Traceback (most recent call last): File "<stdin>", line 1, in <module> File "/usr/local/spark/python/pyspark/sql/readwriter.py", line 139, in load return self._df(self._jreader.load()) File "/usr/local/spark/python/lib/py4j-0.9-src.zip/py4j/java_gateway.py", line 813, in __call__ File "/usr/local/spark/python/pyspark/sql/utils.py", line 45, in deco return f(*a, **kw) File "/usr/local/spark/python/lib/py4j-0.9-src.zip/py4j/protocol.py", line 308, in get_return_value py4j.protocol.Py4JJavaError: An error occurred while calling o23.load. : java.sql.SQLException: No suitable driver at java.sql.DriverManager.getDriver(DriverManager.java:278) at org.apache.spark.sql.execution.datasources.jdbc.JdbcUtils$$anonfun$2.apply(JdbcUtils.scala:50) at org.apache.spark.sql.execution.datasources.jdbc.JdbcUtils$$anonfun$2.apply(JdbcUtils.scala:50) at scala.Option.getOrElse(Option.scala:120) at org.apache.spark.sql.execution.datasources.jdbc.JdbcUtils$.createConnectionFactory(JdbcUtils.scala:49) at org.apache.spark.sql.execution.datasources.jdbc.JDBCRDD$.resolveTable(JDBCRDD.scala:120) at org.apache.spark.sql.execution.datasources.jdbc.JDBCRelation.<init>(JDBCRelation.scala:91) at org.apache.spark.sql.execution.datasources.jdbc.DefaultSource.createRelation(DefaultSource.scala:57) at org.apache.spark.sql.execution.datasources.ResolvedDataSource$.apply(ResolvedDataSource.scala:158) at org.apache.spark.sql.DataFrameReader.load(DataFrameReader.scala:119) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at py4j.reflection.MethodInvoker.invoke(MethodInvoker.java:231) at py4j.reflection.ReflectionEngine.invoke(ReflectionEngine.java:381) at py4j.Gateway.invoke(Gateway.java:259) at py4j.commands.AbstractCommand.invokeMethod(AbstractCommand.java:133) at py4j.commands.CallCommand.execute(CallCommand.java:79) at py4j.GatewayConnection.run(GatewayConnection.java:209) at java.lang.Thread.run(Thread.java:744) >>>
这是我到目前为止尝试过的:
下载mysql-connector-java-5.0.8-bin.jar,并放入/usr/local/spark/lib/。它仍然是相同的错误。
mysql-connector-java-5.0.8-bin.jar
/usr/local/spark/lib/
t.py像这样创建:
t.py
from pyspark import SparkContext
from pyspark.sql import SQLContext
sc = SparkContext(appName=”PythonSQL”) sqlContext = SQLContext(sc) df = sqlContext.read.format(“jdbc”).option(“url”,url).option(“dbtable”,”people”).load()
df.printSchema() countsByAge = df.groupBy(“age”).count() countsByAge.show() countsByAge.write.format(“json”).save(“file:///usr/local/mysql/mysql-connector-java-5.0.8/db.json”)
然后,我尝试了spark-submit --conf spark.executor.extraClassPath=mysql-connector- java-5.0.8-bin.jar --driver-class-path mysql-connector-java-5.0.8-bin.jar --jars mysql-connector-java-5.0.8-bin.jar --master local[4] t.py。结果仍然相同。
spark-submit --conf spark.executor.extraClassPath=mysql-connector- java-5.0.8-bin.jar --driver-class-path mysql-connector-java-5.0.8-bin.jar --jars mysql-connector-java-5.0.8-bin.jar --master local[4] t.py
pyspark --conf spark.executor.extraClassPath=mysql-connector-java-5.0.8-bin.jar --driver-class-path mysql-connector-java-5.0.8-bin.jar --jars mysql-connector-java-5.0.8-bin.jar --master local[4] t.py
在所有这些过程中,mysql正在运行。这是我的操作系统信息:
# rpm --query centos-release centos-release-6-5.el6.centos.11.2.x86_64
Hadoop版本是2.6。
现在我不打算下一步去了,所以我希望有人可以提供一些建议,谢谢!
当我尝试将脚本写入MySQL时,我遇到了“ java.sql.SQLException:没有合适的驱动程序”。
这是我为解决此问题所做的工作。
在script.py中
df.write.jdbc(url="jdbc:mysql://localhost:3333/my_database" "?user=my_user&password=my_password", table="my_table", mode="append", properties={"driver": 'com.mysql.jdbc.Driver'})
然后我以这种方式运行了火花提交
SPARK_HOME=/usr/local/Cellar/apache-spark/1.6.1/libexec spark-submit --packages mysql:mysql-connector-java:5.1.39 ./script.py
请注意,SPARK_HOME特定于spark的安装位置。对于您的环境,https://github.com/sequenceiq/docker- spark/blob/master/README.md可能会有所帮助。
如果以上所有内容都令人困惑,请尝试以下操作: 在t.py中替换
sqlContext.read.format("jdbc").option("url",url).option("dbtable","people").load()
与
sqlContext.read.format("jdbc").option("dbtable","people").option("driver", 'com.mysql.jdbc.Driver').load()
并运行
spark-submit --packages mysql:mysql-connector-java:5.1.39 --master local[4] t.py