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SCALA: Function to load the Data From Data Frame to CSV File using Scala

Hi All, 

 Below is the code which can be created as csv.scala file and can be called inside your MAIN Scala function to push the data from Data Frame to CSV files.


import au.com.bytecode.opencsv.CSVWriter

import java.time.format.DateTimeFormatter

import org.apache.commons.io.FilenameUtils

import java.io.FileWriter

 

object CSVExport {

 

  def exportCSVFile (oracleUser: String,oraclePassword: String,oracleURL: String,oracleOutPutFilePath:String,oracleOutPutFileDateFormat:String,oracleQueryFilePath:String): Unit = {

 

    /* Read date part from the date pattern*/

    val dateNow: String = DateTimeFormatter.ofPattern(oracleOutPutFileDateFormat).format(java.time.LocalDate.now)

 

    /* Reconstruct the new file name*/

    val basename = FilenameUtils.getBaseName(oracleOutPutFilePath)

    val extension = FilenameUtils.getExtension(oracleOutPutFilePath)

    val path = FilenameUtils.getFullPath(oracleOutPutFilePath)

    //println(path,basename,dateNow,extension)

    val newFileName = path + "\\" + basename + "_" + dateNow + "." + extension

    //println(newFileName)

 

    /* Read the query from the file*/

    val queryString = scala.io.Source.fromFile(oracleQueryFilePath).mkString

    //print(queryString)

 

    /* Connect to Oracle DB and run the query and save to results set*/

    val conExport = OracleConnect.connJdbc(oracleUser, oraclePassword, oracleURL)

    val statementExport = conExport.createStatement()

    statementExport.setFetchSize(1000)

    val resultSet: java.sql.ResultSet = statementExport.executeQuery(queryString)

 

    /* Write the result set to CSV file*/

    val csvWriter = new CSVWriter(new FileWriter(newFileName), ',')

    csvWriter.writeAll(resultSet, true)

 

    csvWriter.close()

  }

}

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