title: Duplicate column name in spark read csv
body: <p>I read csv file, which has a duplicate column. </p>
  
  <p>I want to preserve the name of the column in dataframe.</p>
  
  <p>I tried to add this option in my sparkcontext conf <strong>spark.sql.caseSensitive</strong> and put it <strong>true</strong> , but unfortunately it has no effect.</p>
  
  <p>The duplicate column name is NU_CPTE. Spark tried to rename it by adding number of column 0, 7</p>
  
  <p><strong>NU_CPTE0|CD_EVT_FINANCIER|TYP_MVT_ELTR|DT_OPERN_CLI|LI_MVT_ELTR|    MT_OPERN_FINC|FLSENS|NU_CPTE7</strong></p>
  
  <pre><code>SparkSession spark= SparkSession
                  .builder()
                  .master("local[2]")
                  .appName("Application Test")
                  .getOrCreate();    
  
  spark.sparkContext().getConf().set("spark.sql.caseSensitive","true"); 
  
  Dataset&lt;Row&gt; df=spark.read().option("header","true").option("delimiter",";").csv("FILE_201701.csv");
  
  df.show(10);
  </code></pre>
  
  <p>I want something like this as result:</p>
  
  <p><strong>NU_CPTE|CD_EVT_FINANCIER|TYP_MVT_ELTR|DT_OPERN_CLI|LI_MVT_ELTR|    MT_OPERN_FINC|FLSENS|NU_CPTE</strong></p>