diff --git a/src/main/java/org/gcube/dataaccess/databases/utils/DatabaseManagement.java b/src/main/java/org/gcube/dataaccess/databases/utils/DatabaseManagement.java
index 8faf488..6dc65c9 100644
--- a/src/main/java/org/gcube/dataaccess/databases/utils/DatabaseManagement.java
+++ b/src/main/java/org/gcube/dataaccess/databases/utils/DatabaseManagement.java
@@ -112,25 +112,25 @@ public class DatabaseManagement {
 	private String convertToJavaType(String type, String val) throws Exception {
 
 		type = type.toLowerCase();
-		
-//		 AnalysisLogger.getLogger()
-//					 .debug("In DatabaseManagement->type: "
-//					 + type);
-		
+
+		// AnalysisLogger.getLogger()
+		// .debug("In DatabaseManagement->type: "
+		// + type);
+
 		String valConverted = val;
-		
-//		AnalysisLogger.getLogger()
-//		 .debug("In DatabaseManagement->val: "
-//		 + valConverted);
+
+		// AnalysisLogger.getLogger()
+		// .debug("In DatabaseManagement->val: "
+		// + valConverted);
 
 		try {
 
 			// parse to Long
 			valConverted = "" + Long.parseLong(valConverted);
 
-//			 AnalysisLogger.getLogger()
-//			 .debug("In DatabaseManagement->parsed value Long: "
-//			 + valConverted);
+			// AnalysisLogger.getLogger()
+			// .debug("In DatabaseManagement->parsed value Long: "
+			// + valConverted);
 
 		}
 
@@ -160,9 +160,9 @@ public class DatabaseManagement {
 						valConverted = "" + Double.parseDouble(valConverted);
 
 						// // check the parsed value
-//						 AnalysisLogger.getLogger().debug(
-//						 "In DatabaseManagement->parsed value Double: "
-//						 + valConverted);
+						// AnalysisLogger.getLogger().debug(
+						// "In DatabaseManagement->parsed value Double: "
+						// + valConverted);
 
 					}
 
@@ -171,24 +171,24 @@ public class DatabaseManagement {
 						valConverted = "" + Float.parseFloat(valConverted);
 
 						// // check the parsed value
-//						 AnalysisLogger.getLogger().debug(
-//						 "In DatabaseManagement->parsed value Float: "
-//						 + valConverted);
+						// AnalysisLogger.getLogger().debug(
+						// "In DatabaseManagement->parsed value Float: "
+						// + valConverted);
 
 					}
 
-					if (((type.contains("string")))||(type.contains("varchar")) || (type.contains("char"))
-							|| (type.contains("text")) || (type
-								.contains("character varying"))) {
-						
-						valConverted= "\"" + valConverted + "\"";
-						
+					if (((type.contains("string")))
+							|| (type.contains("varchar"))
+							|| (type.contains("char"))
+							|| (type.contains("text"))
+							|| (type.contains("character varying"))) {
+
+						valConverted = "\"" + valConverted + "\"";
+
 						// // check the parsed value
-//						 AnalysisLogger.getLogger().debug(
-//						 "In DatabaseManagement->parsed value string: "
-//						 + valConverted);
-						
-						
+						// AnalysisLogger.getLogger().debug(
+						// "In DatabaseManagement->parsed value string: "
+						// + valConverted);
 
 					}
 
@@ -343,38 +343,22 @@ public class DatabaseManagement {
 		AnalysisLogger.getLogger().debug(
 				"In DatabaseManagement->store table in a file");
 
-		// store table in a file
-		// writeQueryResultIntoFile(results);
-
-		// writeSampleTableIntoFile(results, tableName, schemaName);
-
-		String FileName = pathFile + "QueryResult.csv";
-
 		// List<String> listColumnNames = getColumnNamesTable(tableName,
 		// schemaName);
 
 		// to retrieve datatype columns of a table
-
 		List<String> DataTypeColumns = null;
 
-		// write the result in the file and in the map
-
-		AnalysisLogger.getLogger().debug(
-				"In DatabaseManagement->writing the result in the file: "
-						+ FileName);
-
-		file = new File(FileName);
-
-		out = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(
-				file), "UTF-8"));
-
-		// String header = null;
-
-		// writeTableIntoFile(results, DataTypeColumns, header, tableName,
-		// schemaName,
-		// FileName);
-
-		writeTableIntoFile(results, DataTypeColumns);
+		// // store table in a file
+		// String FileName = pathFile + "QueryResult.csv";
+		// // write the result in the file and in the map
+		// AnalysisLogger.getLogger().debug(
+		// "In DatabaseManagement->writing the result in the file: "
+		// + FileName);
+		// file = new File(FileName);
+		// out = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(
+		// file), "UTF-8"));
+		// writeTableIntoFile(results, DataTypeColumns);
 
 		return results;
 
@@ -610,13 +594,14 @@ public class DatabaseManagement {
 	}
 
 	// Method that returns the estimated number of rows
-	public long getNumberOfRows(String tablename, String schemaName) throws Exception {
+	public long getNumberOfRows(String tablename, String schemaName)
+			throws Exception {
 
 		long rows;
 
 		rows = op.calculateElements(connection, DBType, tablename, schemaName,
 				sourceDBSession);
-		
+
 		AnalysisLogger.getLogger().debug(
 				"DatabaseManagement->rows' number calculated: " + rows);
 
@@ -718,23 +703,7 @@ public class DatabaseManagement {
 		out = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(
 				file), "UTF-8"));
 
-		// mapResult.put("HEADERS", header);
-		//
-		// out.write(header);
-		// out.newLine();
-
-		// writeTableIntoFile(resultSet, DataTypeColumns, header, tableName,
-		// schemaName,
-		// FileName);
-
-		// writeTableIntoFile(resultSet, DataTypeColumns, tableName,
-		// schemaName,
-		// FileName);
-
-		writeTableIntoFile(resultSet, DataTypeColumns);
-
-		// return resultSet;
-
+		// writeTableIntoFile(resultSet, DataTypeColumns);
 	}
 
 	/**
@@ -758,7 +727,6 @@ public class DatabaseManagement {
 
 		AnalysisLogger.getLogger().debug(
 				"DatabaseManagement->starting the Sample on table operation");
-
 		AnalysisLogger.getLogger().debug(
 				"DatabaseManagement->retrieving the first 100 rows");
 
@@ -778,57 +746,27 @@ public class DatabaseManagement {
 		AnalysisLogger.getLogger().debug(
 				"In DatabaseManagement->store table in a file");
 
-		// store table in a file
-
-		// writeSampleTableIntoFile(resultSet, tableName, schemaName);
-
-		String FileName = pathFile + "SampleResult.csv";
-
 		// to recover columns names list
 		List<String> listColumns = sampler.getListColumns();
-		// String header = "";
 
 		for (int i = 0; i < listColumns.size(); i++) {
-
 			if (i != listColumns.size() - 1) {
-
 				header = header + listColumns.get(i) + ", ";
-
 			} else {
-
 				header = header + listColumns.get(i);
-
 			}
 		}
 
-		// write the result in the file and in the map
-
-		AnalysisLogger.getLogger().debug(
-				"In DatabaseManagement->writing the result in the file: "
-						+ FileName);
-
-		file = new File(FileName);
-
-		out = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(
-				file), "UTF-8"));
-
-		// mapResult.put("HEADERS", header);
-		//
-		// out.write(header);
-		// out.newLine();
-
-		// System.out.println("HEADER:" + header);
-
-		// writeTableIntoFile(resultSet, DataTypeColumns, header, tableName,
-		// schemaName,
-		// FileName);
-		// writeTableIntoFile(resultSet, DataTypeColumns, tableName, schemaName,
-		// FileName);
-
-		writeTableIntoFile(resultSet, DataTypeColumns);
-
-		// return the first 100 rows
-		// return resultSet;
+		// // store table in a file
+		// String FileName = pathFile + "SampleResult.csv";
+		// // write the result in the file and in the map
+		// AnalysisLogger.getLogger().debug(
+		// "In DatabaseManagement->writing the result in the file: "
+		// + FileName);
+		// file = new File(FileName);
+		// out = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(
+		// file), "UTF-8"));
+		// writeTableIntoFile(resultSet, DataTypeColumns);
 
 	}
 
@@ -853,7 +791,6 @@ public class DatabaseManagement {
 		AnalysisLogger
 				.getLogger()
 				.debug("DatabaseManagement->starting the Random Sample on table operation");
-
 		AnalysisLogger.getLogger().debug(
 				"DatabaseManagement->retrieving 100 rows");
 
@@ -861,7 +798,6 @@ public class DatabaseManagement {
 		List<String> DataTypeColumns = getDataTypeColumns(tableName, schemaName);
 
 		if (estimatedRows == 0) {
-
 			estimatedRows = getNumberOfRows(tableName, schemaName);
 		}
 
@@ -878,14 +814,7 @@ public class DatabaseManagement {
 		AnalysisLogger.getLogger().debug(
 				"In DatabaseManagement->store table in a file");
 
-		// store table in a file
-
-		// writeSampleTableIntoFile(resultSet, tableName, schemaName);
-
-		String FileName = pathFile + "SampleResult.csv";
-
 		// to recover columns names list
-
 		List<String> listColumns = sampler.getListColumns();
 
 		// //print check
@@ -897,44 +826,23 @@ public class DatabaseManagement {
 		// String header = "";
 
 		for (int i = 0; i < listColumns.size(); i++) {
-
 			if (i != listColumns.size() - 1) {
-
 				header = header + listColumns.get(i) + ", ";
-
 			} else {
-
 				header = header + listColumns.get(i);
-
 			}
 		}
 
-		// write the result in the file and in the map
-
-		AnalysisLogger.getLogger().debug(
-				"In DatabaseManagement->writing the result in the file: "
-						+ FileName);
-
-		file = new File(FileName);
-
-		out = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(
-				file), "UTF-8"));
-
-		// mapResult.put("HEADERS", header);
-		//
-		// out.write(header);
-		// out.newLine();
-
-		// writeTableIntoFile(resultSet, DataTypeColumns, header, tableName,
-		// schemaName,
-		// FileName);
-
-		// writeTableIntoFile(resultSet, DataTypeColumns, tableName, schemaName,
-		// FileName);
-
-		writeTableIntoFile(resultSet, DataTypeColumns);
-
-		// return resultSet;
+//		// store table in a file
+//		String FileName = pathFile + "SampleResult.csv";
+//		// write the result in the file and in the map
+//		AnalysisLogger.getLogger().debug(
+//				"In DatabaseManagement->writing the result in the file: "
+//						+ FileName);
+//		file = new File(FileName);
+//		out = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(
+//				file), "UTF-8"));
+//		writeTableIntoFile(resultSet, DataTypeColumns);
 
 	}
 
@@ -943,237 +851,188 @@ public class DatabaseManagement {
 	// List<String> DataTypeColumns, String tableName, String schemaName,
 	// String FileName) throws Exception {
 
-	// write the table result in the file and build the map of results
-	private void writeTableIntoFile(List<Object> result,
-			List<String> DataTypeColumns) throws Exception {
-
-		// // file that will contain result
-		// BufferedWriter out;
-		//
-		// // String fileName;
-		//
-		// // fileName = "./cfg/" + "table.txt";
-		// // fileName = "./files/" + "table.txt";
-		//
-		// // fileName =
-		// //
-		// "/home/loredana/workspace/DatabasesResourcesManagerAlgorithms/cfg/"
-		// // + "SampleOnTable.txt";
-		//
-		// // fileName = "./files/" + "SmartSampleOnTable.txt";
-		// // File file = new File(fileName);
-		//
-		// AnalysisLogger.getLogger().debug(
-		// "In DatabaseManagement->writing the result in the file: "
-		// + FileName);
-		//
-		// file = new File(FileName);
-		//
-		// // FileWriter fw = new FileWriter(file.getAbsoluteFile());
-		// // out = new BufferedWriter(fw);
-		//
-		// out = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(
-		// file), "UTF-8"));
-		//
-		// // mapResult.put("HEADER", header);
-		//
-		// out.write(header);
-		// out.newLine();
-
-		// to get columns names and result
-
-		// write headers in the file
-
-		// to recover columns names
-
-		if (header.equals("")) {
-			ArrayList<String> listKeys = new ArrayList<String>(
-					((LinkedHashMap<String, Object>) (result.get(0))).keySet());
-
-			for (int i = 0; i < listKeys.size(); i++) {
-
-				if (i != listKeys.size() - 1) {
-
-					header = header + listKeys.get(i) + ", ";
-
-				} else {
-
-					header = header + listKeys.get(i);
-
-				}
-			}
-
-		}
-
-//		 // print check
-//		 AnalysisLogger.getLogger().debug(
-//		 "DatabaseManagement->HEADERS: " + header);
-
-		out.write(header);
-		out.newLine();
-
-		mapResult.put("HEADERS", header);
-
-		// //print check values
-		// AnalysisLogger.getLogger().debug(
-		// "DatabaseManagement->columns names: " + listKeys);
-
-		if (result != null && result.size() != 0) {
-
-			// // write operation in the file
-			for (int i = 0; i < result.size(); i++) {
-
-				String RowString = "";
-
-				Object element = result.get(i);
-
-				//arraylist in which each element is a row result
-				ArrayList<Object> listvalues = new ArrayList<Object>(
-						((LinkedHashMap<String, Object>) element).values());
-
-				// // print check
-				// AnalysisLogger.getLogger().debug(
-				// "DatabaseManagement->values: " + listvalues);
-
-				//each row could have several column values
-				Object[] row = listvalues.toArray();
-
-				if (row.length >= 1) {
-
-					for (int j = 0; j < row.length; j++) {
-
-						if (row[j] == null) {
-							row[j] = "";
-						}
-
-						// to parse the obtained results in order to align
-						// number
-						// values with those of postgres
-						String original = row[j].toString();
-
-//						 // check value
-//						 AnalysisLogger.getLogger().debug(
-//						 "In DatabaseManagement->original value: "
-//						 + original);
-
-						String parsed = "" + row[j];
-
-						if (original != "") {
-							// convert database datatypes to Java datatypes
-							if (DataTypeColumns == null
-									|| DataTypeColumns.size() == 0)
-								parsed = convertToJavaType(row[j].getClass()
-										.getName(), parsed);
-							else
-								parsed = convertToJavaType(
-										DataTypeColumns.get(j), parsed);
-						}
-
-						// // check value
-						// AnalysisLogger.getLogger().debug(
-						// "In DatabaseManagement->row: " + (i + 1)
-						// + " column: " + (j + 1) + " value= "
-						// + parsed);
-
-						// write in a file
-
-						if (j != row.length - 1) {
-
-//							out.write("\"" + parsed + "\"");
-
-//							out.write(",");
-							out.write(parsed);
-							out.write(",");
-							
-							// System.out.println("write column : " + j);
-							// RowString = RowString + parsed + " ";
-							if (j == 0) {
-								RowString = parsed;
-							} else {
-
-								RowString = RowString + "," + parsed;
-							}
-
-						}
-						if (j == row.length - 1) {
-
-//							out.write("\"" + parsed + "\"");
-//							out.newLine();
-							
-							out.write(parsed);
-							out.newLine();
-							
-							// to add a row to the map
-							if (row.length ==1){
-								RowString = parsed;	
-							}else{
-								RowString = RowString + "," + parsed;
-							}
-
-							// to add a row to the map
-//							RowString = RowString + "," + parsed;
-							// mapSampleTableResult.put(String.valueOf(i),
-							// RowString);
-
-							// // check value row
-//							 AnalysisLogger.getLogger().debug(
-//							 "writing the value: " + RowString + " key: "
-//							 + String.valueOf(i));
-
-							// mapResult.put(Integer.valueOf(i), RowString);
-							mapResult.put(String.valueOf(i), RowString);
-
-						}
-
-					}
-				} 
-//				else if (result.size() == 1) {
-//
-//					// Object RowElement = (Object) result.get(0);
-//
-//					if (row[0] == null) {
-//						row[0] = "";
-//					}
-//
-//					// to parse the obtained results in order to align
-//					// number
-//					// values with those of postgres
-//					String original = row[0].toString();
-//
-//					// // check value
-//					// AnalysisLogger.getLogger().debug(
-//					// "In DatabaseManagement->original value: "
-//					// + original);
-//
-//					String parsed = "" + row[0];
-//
-//					if (original != "") {
-//						// convert database datatypes to Java datatypes
-//						if (DataTypeColumns == null
-//								|| DataTypeColumns.size() == 0)
-//							parsed = convertToJavaType(row[0].getClass()
-//									.getName(), parsed);
-//						else
-//							parsed = convertToJavaType(DataTypeColumns.get(0),
-//									parsed);
-//					}
-//
-//					out.write(row[0].toString());
-//					out.newLine();
-//
-//					// to add a row to the map
-//					mapResult.put(String.valueOf(i), row[0].toString());
-//
-//				}
-
-			}
-
-		}
-
-		// close the file
-		out.close();
-
-	}
+	// // write the table result in the file and build the map of results
+	// private void writeTableIntoFile(List<Object> result,
+	// List<String> DataTypeColumns) throws Exception {
+	//
+	// // // file that will contain result
+	// // BufferedWriter out;
+	// // // String fileName;
+	// // // fileName = "./cfg/" + "table.txt";
+	// // // fileName = "./files/" + "table.txt";
+	// // // fileName =
+	// // //
+	// // "/home/loredana/workspace/DatabasesResourcesManagerAlgorithms/cfg/"
+	// // // + "SampleOnTable.txt";
+	// // // fileName = "./files/" + "SmartSampleOnTable.txt";
+	// // // File file = new File(fileName);
+	// // file = new File(FileName);
+	// // out = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(
+	// // file), "UTF-8"));
+	//
+	// // to get columns names and result
+	// // write headers in the file
+	// // to recover columns names
+	// if (header.equals("")) {
+	// ArrayList<String> listKeys = new ArrayList<String>(
+	// ((LinkedHashMap<String, Object>) (result.get(0))).keySet());
+	//
+	// for (int i = 0; i < listKeys.size(); i++) {
+	// if (i != listKeys.size() - 1) {
+	// header = header + listKeys.get(i) + ", ";
+	// } else {
+	// header = header + listKeys.get(i);
+	// }
+	// }
+	// }
+	//
+	// // // print check
+	// // AnalysisLogger.getLogger().debug(
+	// // "DatabaseManagement->HEADERS: " + header);
+	//
+	// out.write(header);
+	// out.newLine();
+	// mapResult.put("HEADERS", header);
+	//
+	// // //print check values
+	// // AnalysisLogger.getLogger().debug(
+	// // "DatabaseManagement->columns names: " + listKeys);
+	//
+	// if (result != null && result.size() != 0) {
+	// // // write operation in the file
+	// for (int i = 0; i < result.size(); i++) {
+	// String RowString = "";
+	// Object element = result.get(i);
+	//
+	// // arraylist in which each element is a row result
+	// ArrayList<Object> listvalues = new ArrayList<Object>(
+	// ((LinkedHashMap<String, Object>) element).values());
+	//
+	// // // print check
+	// // AnalysisLogger.getLogger().debug(
+	// // "DatabaseManagement->values: " + listvalues);
+	//
+	// // each row could have several column values
+	// Object[] row = listvalues.toArray();
+	// if (row.length >= 1) {
+	// for (int j = 0; j < row.length; j++) {
+	// if (row[j] == null) {
+	// row[j] = "";
+	// }
+	// // to parse the obtained results in order to align
+	// // number
+	// // values with those of postgres
+	// String original = row[j].toString();
+	//
+	// // // check value
+	// // AnalysisLogger.getLogger().debug(
+	// // "In DatabaseManagement->original value: "
+	// // + original);
+	//
+	// String parsed = "" + row[j];
+	// if (original != "") {
+	// // convert database datatypes to Java datatypes
+	// if (DataTypeColumns == null
+	// || DataTypeColumns.size() == 0)
+	// parsed = convertToJavaType(row[j].getClass()
+	// .getName(), parsed);
+	// else
+	// parsed = convertToJavaType(
+	// DataTypeColumns.get(j), parsed);
+	// }
+	//
+	// // // check value
+	// // AnalysisLogger.getLogger().debug(
+	// // "In DatabaseManagement->row: " + (i + 1)
+	// // + " column: " + (j + 1) + " value= "
+	// // + parsed);
+	//
+	// // write in a file
+	// if (j != row.length - 1) {
+	// // out.write("\"" + parsed + "\"");
+	// // out.write(",");
+	// out.write(parsed);
+	// out.write(",");
+	//
+	// // System.out.println("write column : " + j);
+	// // RowString = RowString + parsed + " ";
+	// if (j == 0) {
+	// RowString = parsed;
+	// } else {
+	// RowString = RowString + "," + parsed;
+	// }
+	// }
+	// if (j == row.length - 1) {
+	// // out.write("\"" + parsed + "\"");
+	// // out.newLine();
+	// out.write(parsed);
+	// out.newLine();
+	//
+	// // to add a row to the map
+	// if (row.length == 1) {
+	// RowString = parsed;
+	// } else {
+	// RowString = RowString + "," + parsed;
+	// }
+	//
+	// // to add a row to the map
+	// // RowString = RowString + "," + parsed;
+	// // mapSampleTableResult.put(String.valueOf(i),
+	// // RowString);
+	//
+	// // // check value row
+	// // AnalysisLogger.getLogger().debug(
+	// // "writing the value: " + RowString + " key: "
+	// // + String.valueOf(i));
+	//
+	// // mapResult.put(Integer.valueOf(i), RowString);
+	// mapResult.put(String.valueOf(i), RowString);
+	// }
+	// }
+	// }
+	// // else if (result.size() == 1) {
+	// //
+	// // // Object RowElement = (Object) result.get(0);
+	// //
+	// // if (row[0] == null) {
+	// // row[0] = "";
+	// // }
+	// //
+	// // // to parse the obtained results in order to align
+	// // // number
+	// // // values with those of postgres
+	// // String original = row[0].toString();
+	// //
+	// // // // check value
+	// // // AnalysisLogger.getLogger().debug(
+	// // // "In DatabaseManagement->original value: "
+	// // // + original);
+	// //
+	// // String parsed = "" + row[0];
+	// //
+	// // if (original != "") {
+	// // // convert database datatypes to Java datatypes
+	// // if (DataTypeColumns == null
+	// // || DataTypeColumns.size() == 0)
+	// // parsed = convertToJavaType(row[0].getClass()
+	// // .getName(), parsed);
+	// // else
+	// // parsed = convertToJavaType(DataTypeColumns.get(0),
+	// // parsed);
+	// // }
+	// //
+	// // out.write(row[0].toString());
+	// // out.newLine();
+	// //
+	// // // to add a row to the map
+	// // mapResult.put(String.valueOf(i), row[0].toString());
+	// //
+	// // }
+	// }
+	// }
+	// // close the file
+	// out.close();
+	// }
 
 	// to retrieve datatype columns of a table
 	private List<String> getDataTypeColumns(String tableName, String schemaName)