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Hyukjin Kwon commented on SPARK-26383: -------------------------------------- Yea, can you open a PR to fix the error message? > NPE when use DataFrameReader.jdbc with wrong URL > ------------------------------------------------ > > Key: SPARK-26383 > URL: https://issues.apache.org/jira/browse/SPARK-26383 > Project: Spark > Issue Type: Improvement > Components: Spark Core > Affects Versions: 2.4.0 > Reporter: clouds > Priority: Minor > > When passing wrong url to jdbc: > {code:java} > val opts = Map( > "url" -> "jdbc:mysql://localhost/db", > "dbtable" -> "table", > "driver" -> "org.postgresql.Driver" > ) > var df = spark.read.format("jdbc").options(opts).load > {code} > It would throw an NPE instead of complaining about connection failed. (Note > url and driver not matched here) > {code:java} > Exception in thread "main" java.lang.NullPointerException > at > org.apache.spark.sql.execution.datasources.jdbc.JDBCRDD$.resolveTable(JDBCRDD.scala:71) > at > org.apache.spark.sql.execution.datasources.jdbc.JDBCRelation$.getSchema(JDBCRelation.scala:210) > at > org.apache.spark.sql.execution.datasources.jdbc.JdbcRelationProvider.createRelation(JdbcRelationProvider.scala:35) > at > org.apache.spark.sql.execution.datasources.DataSource.resolveRelation(DataSource.scala:318) > at > org.apache.spark.sql.DataFrameReader.loadV1Source(DataFrameReader.scala:223) > at org.apache.spark.sql.DataFrameReader.load(DataFrameReader.scala:211) > at org.apache.spark.sql.DataFrameReader.load(DataFrameReader.scala:167) > {code} > as [postgresql jdbc driver > document|https://jdbc.postgresql.org/development/privateapi/org/postgresql/Driver.html#connect-java.lang.String-java.util.Properties-] > saying, The driver should return "null" if it realizes it is the wrong kind > of driver to connect to the given URL. > while > [ConnectionFactory|https://github.com/apache/spark/blob/e743e848484bf7d97e1b4f33ea83f8520ae7da04/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/jdbc/JDBCRDD.scala#L56] > would not check if conn is null. > {code:java} > val conn: Connection = JdbcUtils.createConnectionFactory(options)() > {code} > and trying to close the conn anyway > {code:java} > try { > ... > } finally { > conn.close() > } > {code} -- This message was sent by Atlassian JIRA (v7.6.3#76005) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org