[SPARK-21648] Confusing assert failure in JDBC source when users misspell the option `partitionColumn`

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.2.0
• Fix Version/s: 2.2.1, 2.3.0
• Component/s: SQL
• Assignee: Xiao Li
• Reporter: Xiao Li
• Created: 07/Aug/17 05:25
• Updated: 07/Aug/17 20:05
• Resolved: 07/Aug/17 20:05

Description

CREATE TABLE mytesttable1 
USING org.apache.spark.sql.jdbc 
  OPTIONS ( 
  url 'jdbc:mysql://${jdbcHostname}:${jdbcPort}/${jdbcDatabase}?user=${jdbcUsername}&password=${jdbcPassword}', 
  dbtable 'mytesttable1', 
  paritionColumn 'state_id', 
  lowerBound '0', 
  upperBound '52', 
  numPartitions '53', 
  fetchSize '10000' 
)

The above option name `paritionColumn` is wrong. That mean, users did not provide the value for `partitionColumn`. In such case, users hit a confusing error

AssertionError: assertion failed
java.lang.AssertionError: assertion failed
	at scala.Predef$.assert(Predef.scala:156)
	at org.apache.spark.sql.execution.datasources.jdbc.JdbcRelationProvider.createRelation(JdbcRelationProvider.scala:39)
	at org.apache.spark.sql.execution.datasources.DataSource.resolveRelation(DataSource.scala:312)