How does spark connect to a relational database through jdbc?

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1 create sparkSession object val sparkSession = SparkSession.builder () .appName ("findIPRel") .getOrCreate () 2 jdbc link create DataFrame object val jdbcDF = sparkSession.read .format ("jdbc") .option ("driver", "org.postgresql.Driver") / / .option ("url", "jdbc:postgresql://121.36.61.51:5432/xsbigdatadb") .option ("dbtable") must be added "ods_proto_log") .option ("user", "postgres") .option ("password", "root@456") .load ()

It should be noted that the driver option must be specified, otherwise even if your classpath contains the jdbc package of the corresponding database, you will not be able to find the appropriate driver error.

3 query the data by dsl through dataFrame object val ori = jdbcDF.select ("srcip", "dstip"). Rdd.map {case Row (col1:String,col2:String) = > (col1,col2) case _ = > (srcIp,srcIp)} 4. Other

Dependency of jdbc newspaper added to pg database in maven

Org.postgresql postgresql 42.2.18

Spark submission specification relies on the jar package to add the-- jars option to the submit command, such as spark-submit-- class com.pxu.spark.core.FindIpRel-- jars. / postgresql-42.2.18.jar-- master spark://master:7077. / sparkLearn-1.0-SNAPSHOT-jar-with-dependencies.jar 192.168.14.17 192.168.73.58 4 hdfs://master:9000/submitTest/output/out3

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