diff --git a/src/main/java/org/gcube/portlets/user/databasesmanager/server/GWTdbManagerServiceImpl.java b/src/main/java/org/gcube/portlets/user/databasesmanager/server/GWTdbManagerServiceImpl.java
index 573e47a..1df3222 100644
--- a/src/main/java/org/gcube/portlets/user/databasesmanager/server/GWTdbManagerServiceImpl.java
+++ b/src/main/java/org/gcube/portlets/user/databasesmanager/server/GWTdbManagerServiceImpl.java
@@ -5,6 +5,7 @@ import java.util.HashMap;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 import java.io.BufferedWriter;
 import java.io.File;
 import java.io.IOException;
@@ -25,6 +26,7 @@ import net.sf.ehcache.config.MemoryUnit;
 import net.sf.ehcache.store.MemoryStoreEvictionPolicy;
 
 import org.apache.regexp.RE;
+import org.apache.xpath.operations.Bool;
 import org.gcube.application.framework.core.session.ASLSession;
 import org.gcube.common.scope.api.ScopeProvider;
 import org.gcube.contentmanager.storageclient.model.protocol.smp.SMPURLConnection;
@@ -83,6 +85,11 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 	private static CacheManager cacheManager;
 	public static List<String> listAlgorithms;
 
+	// variables to check thread execution
+	private static HashMap<String, Boolean> threadsStarted = new HashMap<String, Boolean>();
+	private static boolean endThread = false;
+
+
 	public GWTdbManagerServiceImpl() throws Exception {
 	}
 
@@ -184,6 +191,24 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 	public void destroy() {
 		super.destroy();
 
+		// set endThread variable
+		setEndThreadvariable();
+
+		// set endThread variable
+		// try {
+		// setEndThreadvariable();
+		// logger.info("Thread successfully stopped");
+		//
+		// } catch (InterruptedException e1) {
+		// // TODO Auto-generated catch block
+		// // e1.printStackTrace();
+		// logger.error("dbmanager-> ", e1);
+		// } finally{
+		//
+		// if(t.interrupted()){
+		// logger.info("Thread interrupt");
+		// }
+
 		try {
 
 			CacheManager cacheManager = CacheManager.getInstance();
@@ -211,12 +236,17 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 					e);
 			// e.printStackTrace();
 		}
+		// }
 	}
 
-	private void initVariables() {
+	private void initVariables(ASLSession session) {
 
-		ASLSession session = SessionUtil.getAslSession(this
-				.getThreadLocalRequest().getSession());
+		// // get scope
+		// String scope = session.getScope();
+		//
+		// ThreadLoaderData loader = new ThreadLoaderData(scope);
+		// Thread t = new Thread(loader);
+		// t.start();
 
 		// the result generated in the LoadTables method
 		// List<Result> result = new ArrayList<Result>();
@@ -280,86 +310,114 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 
 		try {
 
+			ASLSession session = SessionUtil.getAslSession(this
+					.getThreadLocalRequest().getSession());
+			// get scope
+			String scope = session.getScope();
+
+			// check if the thread is alreday started
+			Boolean value = getThreadStarted(scope);
+			if ((value == null) || (value.booleanValue() == false)) {
+				ThreadLoaderData loader = new ThreadLoaderData(scope);
+				Thread t = new Thread(loader);
+				t.start();
+
+				logger.info("dbmanager-> Thread created in order to load all data");
+			}
+
 			// initialize variables with application startup
-			initVariables();
-
-			// data input
-			List<Parameter> inputParameters = new ArrayList<Parameter>();
-			// data output
-			List<FileModel> outputParameters = new ArrayList<FileModel>();
-
-			// get algorithmId
-			String algorithmId = ConstantsPortlet.ALGID_GETRESOURCE;
-
-			Parameter maxNumber = new Parameter("MaxNumber", "", "String", "-1");
-			inputParameters.add(maxNumber);
-
-			// check if the value is in cache. If data does not exist in cache
-			// the computation is started otherwise data are retrieved from
-			// cache.
-
-			// get data from cache
-			// check if data exist considering as key the input parameters
-			// String key = inputParameters.get(0).getDefaultValue();
-			String key = "listResources";
-
-			// System.out.println("***KEY: " + key);
-			net.sf.ehcache.Element dataFromCache = getDataFromCache(key);
-
-			Object value = null;
-			if (dataFromCache != null) {
-				value = dataFromCache.getObjectValue();
-				// System.out.println("***GETTING DATA FROM CACHE");
-			}
-			if (value != null) {
-				outputParameters = (List<FileModel>) value;
-			} else {
-
-				// start the computation
-				// System.out.println("***STARTING THE COMPUTATION");
-				// create data structure for data output
-				ComputationOutput outputData = new ComputationOutput();
-				// computationId
-				String computationId = startComputation(algorithmId,
-						inputParameters, outputData);
-
-				// print check
-				// retrieve data
-				// logger.info("output data retrieved");
-
-				// data output
-				LinkedHashMap<String, String> mapValues = new LinkedHashMap<String, String>();
-				mapValues = outputData.getMapValues();
-
-				for (int i = 0; i < mapValues.size(); i++) {
-					FileModel obj = new FileModel(mapValues.get(String
-							.valueOf(i)));
-					// obj.setIsLoaded(true);
-					outputParameters.add(obj);
-				}
-
-				if (outputParameters != null && outputParameters.size() != 0) {
-					// put data in cache
-					net.sf.ehcache.Element dataToCache = new net.sf.ehcache.Element(
-							key, outputParameters);
-
-					insertDataIntoCache(dataToCache);
-				}
-			}
-
-			return outputParameters;
+			initVariables(session);
+			return recoverResources(scope);
 
 		} catch (Exception e) {
-			// e.printStackTrace();
-			// throw new Exception("Failed to load data. " + e);
 			logger.error("dbmanager-> ", e);
-			if (!(e instanceof StatisticalManagerException)) {
-				// GWT can't serialize all exceptions
-				throw new Exception(
-						"Error in server while loading data. Exception: " + e);
-			}
 			throw e;
+
 		}
+
+		// try {
+		//
+		// // initialize variables with application startup
+		// initVariables();
+		//
+		// // data input
+		// List<Parameter> inputParameters = new ArrayList<Parameter>();
+		// // data output
+		// List<FileModel> outputParameters = new ArrayList<FileModel>();
+		//
+		// // get algorithmId
+		// String algorithmId = ConstantsPortlet.ALGID_GETRESOURCE;
+		//
+		// Parameter maxNumber = new Parameter("MaxNumber", "", "String", "-1");
+		// inputParameters.add(maxNumber);
+		//
+		// // check if the value is in cache. If data does not exist in cache
+		// // the computation is started otherwise data are retrieved from
+		// // cache.
+		//
+		// // get data from cache
+		// // check if data exist considering as key the input parameters
+		// // String key = inputParameters.get(0).getDefaultValue();
+		// String key = "listResources";
+		//
+		// // System.out.println("***KEY: " + key);
+		// net.sf.ehcache.Element dataFromCache = getDataFromCache(key);
+		//
+		// Object value = null;
+		// if (dataFromCache != null) {
+		// value = dataFromCache.getObjectValue();
+		// // System.out.println("***GETTING DATA FROM CACHE");
+		// }
+		// if (value != null) {
+		// outputParameters = (List<FileModel>) value;
+		// } else {
+		//
+		// // start the computation
+		// // System.out.println("***STARTING THE COMPUTATION");
+		// // create data structure for data output
+		// ComputationOutput outputData = new ComputationOutput();
+		// // computationId
+		// String computationId = startComputation(algorithmId,
+		// inputParameters, outputData, "");
+		//
+		// // print check
+		// // retrieve data
+		// // logger.info("output data retrieved");
+		//
+		// // data output
+		// LinkedHashMap<String, String> mapValues = new LinkedHashMap<String,
+		// String>();
+		// mapValues = outputData.getMapValues();
+		//
+		// for (int i = 0; i < mapValues.size(); i++) {
+		// FileModel obj = new FileModel(mapValues.get(String
+		// .valueOf(i)));
+		// // obj.setIsLoaded(true);
+		// outputParameters.add(obj);
+		// }
+		//
+		// if (outputParameters != null && outputParameters.size() != 0) {
+		// // put data in cache
+		// net.sf.ehcache.Element dataToCache = new net.sf.ehcache.Element(
+		// key, outputParameters);
+		//
+		// insertDataIntoCache(dataToCache);
+		// }
+		// }
+		//
+		// return outputParameters;
+		//
+		// } catch (Exception e) {
+		// // e.printStackTrace();
+		// // throw new Exception("Failed to load data. " + e);
+		// logger.error("dbmanager-> ", e);
+		// if (!(e instanceof StatisticalManagerException)) {
+		// // GWT can't serialize all exceptions
+		// throw new Exception(
+		// "Error in server while loading data. Exception: " + e);
+		// }
+		// throw e;
+		// }
 	}
 
 	// to get information about databases of a resource
@@ -372,97 +430,112 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 			throw new SessionExpiredException();
 
 		try {
-			// data input
-			List<Parameter> inputParameters = new ArrayList<Parameter>();
-			// data output
-			LinkedHashMap<String, FileModel> outputParameters = new LinkedHashMap<String, FileModel>();
-
-			String algorithmId = ConstantsPortlet.ALGID_GETDBINFO;
-
-			// print check
-			logger.info("dbmanager-> ResourceName: " + resourceName);
-
-			if ((resourceName == null) || (resourceName.equals(""))) {
-				throw new Exception("Unable to load data");
-			}
-
-			Parameter resource = new Parameter("ResourceName", "", "String", "");
-			inputParameters.add(resource);
-			inputParameters.get(0).setValue(resourceName);
-
-			// get data from cache
-			// check if data exist considering as key the input parameters
-			String key = inputParameters.get(0).getValue();
-
-			// System.out.println("***KEY: " + key);
-			net.sf.ehcache.Element dataFromCache = getDataFromCache(key);
-
-			Object value = null;
-			if (dataFromCache != null) {
-				value = dataFromCache.getObjectValue();
-			}
-			if (value != null) {
-				outputParameters = (LinkedHashMap<String, FileModel>) value;
-				// System.out.println("***GETTING DATA FROM CACHE");
-			} else {
-
-				// start the computation
-				// System.out.println("***STARTING THE COMPUTATION");
-				// create data structure
-				ComputationOutput outputData = new ComputationOutput();
-				// computation id
-				String computationId = startComputation(algorithmId,
-						inputParameters, outputData);
-
-				// print check
-				// retrieve data
-				// logger.info("output data retrieved");
-
-				// data output values
-				LinkedHashMap<String, String> mapValues = new LinkedHashMap<String, String>();
-				// data output keys
-				LinkedHashMap<String, String> mapKeys = new LinkedHashMap<String, String>();
-
-				mapValues = outputData.getMapValues();
-				mapKeys = outputData.getmapKeys();
-
-				for (int i = 0; i < mapValues.size(); i++) {
-					FileModel obj = new FileModel(mapValues.get(String
-							.valueOf(i)));
-					// obj.setIsLoaded(true);
-
-					// print check
-					// logger.info("value: " +
-					// mapValues.get(String.valueOf(i)));
-					// logger.info("key: " +
-					// mapKeys.get(String.valueOf(i)));
-					outputParameters.put(mapKeys.get(String.valueOf(i)), obj);
-				}
-
-				// write data in cache
-				if (outputParameters != null && outputParameters.size() != 0) {
-					// put data in cache
-					net.sf.ehcache.Element dataToCache = new net.sf.ehcache.Element(
-							inputParameters.get(0).getValue(), outputParameters);
-
-					insertDataIntoCache(dataToCache);
-				}
-			}
-
-			return outputParameters;
 
+			ASLSession session = SessionUtil.getAslSession(this
+					.getThreadLocalRequest().getSession());
+			// get scope
+			String scope = session.getScope();
+			return recoverDatabases(scope, resourceName);
 		} catch (Exception e) {
-			// e.printStackTrace();
-			// throw new Exception("Failed to load data " + );
 			logger.error("dbmanager-> ", e);
-
-			if (!(e instanceof StatisticalManagerException)) {
-				// GWT can't serialize all exceptions
-				throw new Exception(
-						"Error in server while loading data. Exception: " + e);
-			}
 			throw e;
 		}
+
+		// try {
+		// // data input
+		// List<Parameter> inputParameters = new ArrayList<Parameter>();
+		// // data output
+		// LinkedHashMap<String, FileModel> outputParameters = new
+		// LinkedHashMap<String, FileModel>();
+		//
+		// String algorithmId = ConstantsPortlet.ALGID_GETDBINFO;
+		//
+		// // print check
+		// logger.info("dbmanager-> ResourceName: " + resourceName);
+		//
+		// if ((resourceName == null) || (resourceName.equals(""))) {
+		// throw new Exception("Unable to load data");
+		// }
+		//
+		// Parameter resource = new Parameter("ResourceName", "", "String", "");
+		// inputParameters.add(resource);
+		// inputParameters.get(0).setValue(resourceName);
+		//
+		// // get data from cache
+		// // check if data exist considering as key the input parameters
+		// String key = inputParameters.get(0).getValue();
+		//
+		// // System.out.println("***KEY: " + key);
+		// net.sf.ehcache.Element dataFromCache = getDataFromCache(key);
+		//
+		// Object value = null;
+		// if (dataFromCache != null) {
+		// value = dataFromCache.getObjectValue();
+		// }
+		// if (value != null) {
+		// outputParameters = (LinkedHashMap<String, FileModel>) value;
+		// // System.out.println("***GETTING DATA FROM CACHE");
+		// } else {
+		//
+		// // start the computation
+		// // System.out.println("***STARTING THE COMPUTATION");
+		// // create data structure
+		// ComputationOutput outputData = new ComputationOutput();
+		// // computation id
+		// String computationId = startComputation(algorithmId,
+		// inputParameters, outputData);
+		//
+		// // print check
+		// // retrieve data
+		// // logger.info("output data retrieved");
+		//
+		// // data output values
+		// LinkedHashMap<String, String> mapValues = new LinkedHashMap<String,
+		// String>();
+		// // data output keys
+		// LinkedHashMap<String, String> mapKeys = new LinkedHashMap<String,
+		// String>();
+		//
+		// mapValues = outputData.getMapValues();
+		// mapKeys = outputData.getmapKeys();
+		//
+		// for (int i = 0; i < mapValues.size(); i++) {
+		// FileModel obj = new FileModel(mapValues.get(String
+		// .valueOf(i)));
+		// // obj.setIsLoaded(true);
+		//
+		// // print check
+		// // logger.info("value: " +
+		// // mapValues.get(String.valueOf(i)));
+		// // logger.info("key: " +
+		// // mapKeys.get(String.valueOf(i)));
+		// outputParameters.put(mapKeys.get(String.valueOf(i)), obj);
+		// }
+		//
+		// // write data in cache
+		// if (outputParameters != null && outputParameters.size() != 0) {
+		// // put data in cache
+		// net.sf.ehcache.Element dataToCache = new net.sf.ehcache.Element(
+		// inputParameters.get(0).getValue(), outputParameters);
+		//
+		// insertDataIntoCache(dataToCache);
+		// }
+		// }
+		//
+		// return outputParameters;
+		//
+		// } catch (Exception e) {
+		// // e.printStackTrace();
+		// // throw new Exception("Failed to load data " + );
+		// logger.error("dbmanager-> ", e);
+		//
+		// if (!(e instanceof StatisticalManagerException)) {
+		// // GWT can't serialize all exceptions
+		// throw new Exception(
+		// "Error in server while loading data. Exception: " + e);
+		// }
+		// throw e;
+		// }
 	}
 
 	// to get schema for a database
@@ -476,109 +549,123 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 
 		try {
 
-			// data input
-			List<Parameter> inputParameters = new ArrayList<Parameter>();
-			// data output
-			List<FileModel> outputParameters = new ArrayList<FileModel>();
-
-			String algorithmId = ConstantsPortlet.ALGID_GETDBSCHEMA;
-			// print check
-			String rs = dataInput.get("ResourceName");
-			String db = dataInput.get("DatabaseName");
-
-			logger.info("dbmanager-> ResourceName: " + rs);
-			logger.info("dbmanager-> DatabaseName: " + db);
-
-			if ((rs == null) || (rs.equals(""))) {
-				throw new Exception("Unable to load data");
-			}
-			if ((db == null) || (db.equals(""))) {
-				throw new Exception("Unable to load data");
-			}
-
-			// set input parameters
-			Parameter resource = new Parameter("ResourceName", "", "String", "");
-			Parameter database = new Parameter("DatabaseName", "", "String", "");
-			inputParameters.add(resource);
-			inputParameters.add(database);
-
-			inputParameters.get(0).setValue(rs);
-			inputParameters.get(1).setValue(db);
-
-			// print check algorithm input parameters
-			// for (int i = 0; i < inputParameters.size(); i++) {
-			// logger.info(inputParameters.get(i).getName());
-			// }
-
-			// get data from cache
-			// check if data exist considering as key the input parameters
-			String key = inputParameters.get(0).getValue()
-					+ inputParameters.get(1).getValue();
-
-			// System.out.println("key in GETSCHEMA: " + key);
-			net.sf.ehcache.Element dataFromCache = getDataFromCache(key);
-
-			Object value = null;
-			if (dataFromCache != null) {
-				value = dataFromCache.getObjectValue();
-			}
-			if (value != null) {
-				outputParameters = (List<FileModel>) value;
-			} else {
-
-				// start the computation
-				// create data structure
-				ComputationOutput outputData = new ComputationOutput();
-				// computation id
-				String computationId = startComputation(algorithmId,
-						inputParameters, outputData);
-
-				// print check
-				// retrieve data
-				// logger.info("dbmanager-> output data retrieved");
-
-				// data output values
-				LinkedHashMap<String, String> mapValues = new LinkedHashMap<String, String>();
-				// data output keys
-				LinkedHashMap<String, String> mapKeys = new LinkedHashMap<String, String>();
-
-				mapValues = outputData.getMapValues();
-				mapKeys = outputData.getmapKeys();
-
-				for (int i = 0; i < mapValues.size(); i++) {
-					FileModel obj = new FileModel(mapValues.get(String
-							.valueOf(i)));
-					// obj.setIsSchema(true);
-					// obj.setIsLoaded(true);
-					outputParameters.add(obj);
-				}
-
-				// write data in cache
-				if (outputParameters != null && outputParameters.size() != 0) {
-					// put data in cache
-					net.sf.ehcache.Element dataToCache = new net.sf.ehcache.Element(
-							inputParameters.get(0).getValue()
-									+ inputParameters.get(1).getValue(),
-							outputParameters);
-
-					insertDataIntoCache(dataToCache);
-					// DBCache.put(dataToCache);
-				}
-			}
-
-			return outputParameters;
-
+			ASLSession session = SessionUtil.getAslSession(this
+					.getThreadLocalRequest().getSession());
+			// get scope
+			String scope = session.getScope();
+			return recoverSchema(scope, dataInput);
 		} catch (Exception e) {
-			// e.printStackTrace();
-			// throw new Exception("Failed to load data. " + e);
 			logger.error("dbmanager-> ", e);
-			if (!(e instanceof StatisticalManagerException)) {
-				// GWT can't serialize all exceptions
-				throw new Exception(
-						"Error in server while loading data. Exception: " + e);
-			}
 			throw e;
 		}
+
+		// try {
+		//
+		// // data input
+		// List<Parameter> inputParameters = new ArrayList<Parameter>();
+		// // data output
+		// List<FileModel> outputParameters = new ArrayList<FileModel>();
+		//
+		// String algorithmId = ConstantsPortlet.ALGID_GETDBSCHEMA;
+		// // print check
+		// String rs = dataInput.get("ResourceName");
+		// String db = dataInput.get("DatabaseName");
+		//
+		// logger.info("dbmanager-> ResourceName: " + rs);
+		// logger.info("dbmanager-> DatabaseName: " + db);
+		//
+		// if ((rs == null) || (rs.equals(""))) {
+		// throw new Exception("Unable to load data");
+		// }
+		// if ((db == null) || (db.equals(""))) {
+		// throw new Exception("Unable to load data");
+		// }
+		//
+		// // set input parameters
+		// Parameter resource = new Parameter("ResourceName", "", "String", "");
+		// Parameter database = new Parameter("DatabaseName", "", "String", "");
+		// inputParameters.add(resource);
+		// inputParameters.add(database);
+		//
+		// inputParameters.get(0).setValue(rs);
+		// inputParameters.get(1).setValue(db);
+		//
+		// // print check algorithm input parameters
+		// // for (int i = 0; i < inputParameters.size(); i++) {
+		// // logger.info(inputParameters.get(i).getName());
+		// // }
+		//
+		// // get data from cache
+		// // check if data exist considering as key the input parameters
+		// String key = inputParameters.get(0).getValue()
+		// + inputParameters.get(1).getValue();
+		//
+		// // System.out.println("key in GETSCHEMA: " + key);
+		// net.sf.ehcache.Element dataFromCache = getDataFromCache(key);
+		//
+		// Object value = null;
+		// if (dataFromCache != null) {
+		// value = dataFromCache.getObjectValue();
+		// }
+		// if (value != null) {
+		// outputParameters = (List<FileModel>) value;
+		// } else {
+		//
+		// // start the computation
+		// // create data structure
+		// ComputationOutput outputData = new ComputationOutput();
+		// // computation id
+		// String computationId = startComputation(algorithmId,
+		// inputParameters, outputData, scope);
+		//
+		// // print check
+		// // retrieve data
+		// // logger.info("dbmanager-> output data retrieved");
+		//
+		// // data output values
+		// LinkedHashMap<String, String> mapValues = new LinkedHashMap<String,
+		// String>();
+		// // data output keys
+		// LinkedHashMap<String, String> mapKeys = new LinkedHashMap<String,
+		// String>();
+		//
+		// mapValues = outputData.getMapValues();
+		// mapKeys = outputData.getmapKeys();
+		//
+		// for (int i = 0; i < mapValues.size(); i++) {
+		// FileModel obj = new FileModel(mapValues.get(String
+		// .valueOf(i)));
+		// // obj.setIsSchema(true);
+		// // obj.setIsLoaded(true);
+		// outputParameters.add(obj);
+		// }
+		//
+		// // write data in cache
+		// if (outputParameters != null && outputParameters.size() != 0) {
+		// // put data in cache
+		// net.sf.ehcache.Element dataToCache = new net.sf.ehcache.Element(
+		// inputParameters.get(0).getValue()
+		// + inputParameters.get(1).getValue(),
+		// outputParameters);
+		//
+		// insertDataIntoCache(dataToCache);
+		// // DBCache.put(dataToCache);
+		// }
+		// }
+		//
+		// return outputParameters;
+		//
+		// } catch (Exception e) {
+		// // e.printStackTrace();
+		// // throw new Exception("Failed to load data. " + e);
+		// logger.error("dbmanager-> ", e);
+		// if (!(e instanceof StatisticalManagerException)) {
+		// // GWT can't serialize all exceptions
+		// throw new Exception(
+		// "Error in server while loading data. Exception: " + e);
+		// }
+		// throw e;
+		// }
 	}
 
 	// to get tables
@@ -587,126 +674,140 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 
 		try {
 
-			// data input
-			List<Parameter> inputParameters = new ArrayList<Parameter>();
-			// data output
-			List<Result> outputParameters = new ArrayList<Result>();
-
-			String algorithmId = ConstantsPortlet.ALGID_GETTABLES;
-
-			String rs = dataInput.get("ResourceName");
-			String db = dataInput.get("DatabaseName");
-			String scm = dataInput.get("SchemaName");
-
-			// print check
-			logger.info("dbmanager-> ResourceName: " + rs);
-			logger.info("dbmanager-> DatabaseName: " + db);
-			logger.info("dbmanager-> SchemaName: " + scm);
-
-			if ((elementType != null)
-					&& (elementType.equals(ConstantsPortlet.SCHEMA))) {
-				if ((rs == null) || (rs.equals(""))) {
-					throw new Exception("Unable to load data");
-				}
-				if ((db == null) || (db.equals(""))) {
-					throw new Exception("Unable to load data");
-				}
-				if ((scm == null) || (scm.equals(""))) {
-					throw new Exception("Unable to load data");
-				}
-			}
-			if ((elementType != null)
-					&& (elementType.equals(ConstantsPortlet.DATABASE))) {
-				if ((rs == null) || (rs.equals(""))) {
-					throw new Exception("Unable to load data");
-				}
-				if ((db == null) || (db.equals(""))) {
-					throw new Exception("Unable to load data");
-				}
-			}
-
-			// set input parameters
-			Parameter resource = new Parameter("ResourceName", "", "String", "");
-			Parameter database = new Parameter("DatabaseName", "", "String", "");
-			Parameter schema = new Parameter("SchemaName", "", "String", "");
-			inputParameters.add(resource);
-			inputParameters.add(database);
-			inputParameters.add(schema);
-
-			inputParameters.get(0).setValue(rs);
-			inputParameters.get(1).setValue(db);
-			inputParameters.get(2).setValue(scm);
-
-			// get data from cache
-			// check if data exist considering as key the input parameters
-			String key = inputParameters.get(0).getValue()
-					+ inputParameters.get(1).getValue()
-					+ inputParameters.get(2).getValue();
-
-			// System.out.println("***KEY: " + key);
-			net.sf.ehcache.Element dataFromCache = getDataFromCache(key);
-
-			Object value = null;
-			if (dataFromCache != null) {
-				value = dataFromCache.getObjectValue();
-				// System.out.println("***GETTING DATA FROM CACHE");
-			}
-			if (value != null) {
-				outputParameters = (List<Result>) value;
-
-			} else {
-
-				// start computation
-				// create data structure
-				ComputationOutput outputData = new ComputationOutput();
-				// computation id
-				String computationId = startComputation(algorithmId,
-						inputParameters, outputData);
-
-				// print check on retrieving data
-				// logger.info("output data retrieved");
-
-				// data output values
-				LinkedHashMap<String, String> mapValues = new LinkedHashMap<String, String>();
-				// data output keys
-				LinkedHashMap<String, String> mapKeys = new LinkedHashMap<String, String>();
-
-				mapValues = outputData.getMapValues();
-				mapKeys = outputData.getmapKeys();
-
-				for (int i = 0; i < mapValues.size(); i++) {
-					Result row = new Result(String.valueOf(i),
-							mapValues.get(String.valueOf(i)));
-					outputParameters.add(row);
-				}
-
-				// write data in cache
-				if (outputParameters != null && outputParameters.size() != 0) {
-					// put data in cache
-					net.sf.ehcache.Element dataToCache = new net.sf.ehcache.Element(
-							inputParameters.get(0).getValue()
-									+ inputParameters.get(1).getValue()
-									+ inputParameters.get(2).getValue(),
-							outputParameters);
-
-					insertDataIntoCache(dataToCache);
-				}
-
-			}
-			return outputParameters;
-
+			ASLSession session = SessionUtil.getAslSession(this
+					.getThreadLocalRequest().getSession());
+			// get scope
+			String scope = session.getScope();
+			return recoverTables(scope, dataInput, elementType);
 		} catch (Exception e) {
-			// e.printStackTrace();
-			// throw new Exception("Failed to load data. " + e);
-			// logger.error("dbmanager-> ", e);
-
-			if (!(e instanceof StatisticalManagerException)) {
-				// GWT can't serialize all exceptions
-				throw new Exception(
-						"Error in server while loading data. Exception: " + e);
-			}
+			logger.error("dbmanager-> ", e);
 			throw e;
 		}
+
+		// try {
+		//
+		// // data input
+		// List<Parameter> inputParameters = new ArrayList<Parameter>();
+		// // data output
+		// List<Result> outputParameters = new ArrayList<Result>();
+		//
+		// String algorithmId = ConstantsPortlet.ALGID_GETTABLES;
+		//
+		// String rs = dataInput.get("ResourceName");
+		// String db = dataInput.get("DatabaseName");
+		// String scm = dataInput.get("SchemaName");
+		//
+		// // print check
+		// logger.info("dbmanager-> ResourceName: " + rs);
+		// logger.info("dbmanager-> DatabaseName: " + db);
+		// logger.info("dbmanager-> SchemaName: " + scm);
+		//
+		// if ((elementType != null)
+		// && (elementType.equals(ConstantsPortlet.SCHEMA))) {
+		// if ((rs == null) || (rs.equals(""))) {
+		// throw new Exception("Unable to load data");
+		// }
+		// if ((db == null) || (db.equals(""))) {
+		// throw new Exception("Unable to load data");
+		// }
+		// if ((scm == null) || (scm.equals(""))) {
+		// throw new Exception("Unable to load data");
+		// }
+		// }
+		// if ((elementType != null)
+		// && (elementType.equals(ConstantsPortlet.DATABASE))) {
+		// if ((rs == null) || (rs.equals(""))) {
+		// throw new Exception("Unable to load data");
+		// }
+		// if ((db == null) || (db.equals(""))) {
+		// throw new Exception("Unable to load data");
+		// }
+		// }
+		//
+		// // set input parameters
+		// Parameter resource = new Parameter("ResourceName", "", "String", "");
+		// Parameter database = new Parameter("DatabaseName", "", "String", "");
+		// Parameter schema = new Parameter("SchemaName", "", "String", "");
+		// inputParameters.add(resource);
+		// inputParameters.add(database);
+		// inputParameters.add(schema);
+		//
+		// inputParameters.get(0).setValue(rs);
+		// inputParameters.get(1).setValue(db);
+		// inputParameters.get(2).setValue(scm);
+		//
+		// // get data from cache
+		// // check if data exist considering as key the input parameters
+		// String key = inputParameters.get(0).getValue()
+		// + inputParameters.get(1).getValue()
+		// + inputParameters.get(2).getValue();
+		//
+		// // System.out.println("***KEY: " + key);
+		// net.sf.ehcache.Element dataFromCache = getDataFromCache(key);
+		//
+		// Object value = null;
+		// if (dataFromCache != null) {
+		// value = dataFromCache.getObjectValue();
+		// // System.out.println("***GETTING DATA FROM CACHE");
+		// }
+		// if (value != null) {
+		// outputParameters = (List<Result>) value;
+		//
+		// } else {
+		//
+		// // start computation
+		// // create data structure
+		// ComputationOutput outputData = new ComputationOutput();
+		// // computation id
+		// String computationId = startComputation(algorithmId,
+		// inputParameters, outputData, scope);
+		//
+		// // print check on retrieving data
+		// // logger.info("output data retrieved");
+		//
+		// // data output values
+		// LinkedHashMap<String, String> mapValues = new LinkedHashMap<String,
+		// String>();
+		// // data output keys
+		// LinkedHashMap<String, String> mapKeys = new LinkedHashMap<String,
+		// String>();
+		//
+		// mapValues = outputData.getMapValues();
+		// mapKeys = outputData.getmapKeys();
+		//
+		// for (int i = 0; i < mapValues.size(); i++) {
+		// Result row = new Result(String.valueOf(i),
+		// mapValues.get(String.valueOf(i)));
+		// outputParameters.add(row);
+		// }
+		//
+		// // write data in cache
+		// if (outputParameters != null && outputParameters.size() != 0) {
+		// // put data in cache
+		// net.sf.ehcache.Element dataToCache = new net.sf.ehcache.Element(
+		// inputParameters.get(0).getValue()
+		// + inputParameters.get(1).getValue()
+		// + inputParameters.get(2).getValue(),
+		// outputParameters);
+		//
+		// insertDataIntoCache(dataToCache);
+		// }
+		//
+		// }
+		// return outputParameters;
+		//
+		// } catch (Exception e) {
+		// // e.printStackTrace();
+		// // throw new Exception("Failed to load data. " + e);
+		// // logger.error("dbmanager-> ", e);
+		//
+		// if (!(e instanceof StatisticalManagerException)) {
+		// // GWT can't serialize all exceptions
+		// throw new Exception(
+		// "Error in server while loading data. Exception: " + e);
+		// }
+		// throw e;
+		// }
 	}
 
 	// to load tables
@@ -843,6 +944,11 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 			throw new SessionExpiredException();
 
 		try {
+			
+			ASLSession session = SessionUtil.getAslSession(this
+					.getThreadLocalRequest().getSession());
+			// get scope
+			String scope = session.getScope();
 
 			logger.info("dbmanager-> Dialect used for smart correction: "
 					+ language);
@@ -914,7 +1020,7 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 			// parse the query in order to remove spaces
 			String queryParsed = parseQuery(inputParameters.get(5).getValue());
 			// get data sent to client calling the submitQuery
-			String keyData = algorithmId + inputParameters.get(0).getValue()
+			String keyData = scope+algorithmId + inputParameters.get(0).getValue()
 					+ inputParameters.get(1).getValue()
 					+ inputParameters.get(2).getValue()
 					+ inputParameters.get(3).getValue()
@@ -956,7 +1062,7 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 
 				// computation id
 				String computationId = startComputation(algorithmId,
-						inputParameters, outputData, UID);
+						inputParameters, outputData, scope, UID);
 
 				// get JobID
 				if (checkJob(UID)) { // if the computation has not been removed
@@ -1080,7 +1186,15 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 		if (isSessionExpired())
 			throw new SessionExpiredException();
 
+		
+
 		try {
+			
+			ASLSession session = SessionUtil.getAslSession(this
+					.getThreadLocalRequest().getSession());
+			// get scope
+			String scope = session.getScope();
+			
 			// data input
 			List<Parameter> inputParameters = new ArrayList<Parameter>();
 			// output sample result
@@ -1146,12 +1260,12 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 
 			// get data from cache
 			// check if data exist considering as key the input parameters
-			String key = algorithmId + inputParameters.get(0).getValue()
+			String key = scope+algorithmId + inputParameters.get(0).getValue()
 					+ inputParameters.get(1).getValue()
 					+ inputParameters.get(2).getValue()
 					+ inputParameters.get(3).getValue();
 
-			// System.out.println("sampling KEY: " + key);
+//			 System.out.println("sampling KEY: " + key);
 			net.sf.ehcache.Element dataFromCache = getDataFromCache(key);
 
 			Object value = null;
@@ -1170,7 +1284,7 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 				ComputationOutput outputData = new ComputationOutput();
 				// computation id
 				String computationId = startComputation(algorithmId,
-						inputParameters, outputData);
+						inputParameters, outputData, scope);
 
 				// print check on retrieving data
 				// logger.info("output data retrieved");
@@ -1229,6 +1343,11 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 			throw new SessionExpiredException();
 
 		try {
+			ASLSession session = SessionUtil.getAslSession(this
+					.getThreadLocalRequest().getSession());
+			// get scope
+			String scope = session.getScope();
+			
 			// data input
 			List<Parameter> inputParameters = new ArrayList<Parameter>();
 			// output sample result
@@ -1294,7 +1413,7 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 
 			// get data from cache
 			// check if data exist considering as key the input parameters
-			String key = algorithmId + inputParameters.get(0).getValue()
+			String key = scope+algorithmId + inputParameters.get(0).getValue()
 					+ inputParameters.get(1).getValue()
 					+ inputParameters.get(2).getValue()
 					+ inputParameters.get(3).getValue();
@@ -1315,7 +1434,7 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 				ComputationOutput outputData = new ComputationOutput();
 				// computation id
 				String computationId = startComputation(algorithmId,
-						inputParameters, outputData);
+						inputParameters, outputData, scope);
 
 				// print check on retrieving data
 				// logger.info("dbmanager-> output data retrieved");
@@ -1375,6 +1494,11 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 			throw new SessionExpiredException();
 
 		try {
+			ASLSession session = SessionUtil.getAslSession(this
+					.getThreadLocalRequest().getSession());
+			// get scope
+			String scope = session.getScope();
+			
 			// data input
 			List<Parameter> inputParameters = new ArrayList<Parameter>();
 			// output sample result
@@ -1441,7 +1565,7 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 			ComputationOutput outputData = new ComputationOutput();
 			// computation id
 			String computationId = startComputation(algorithmId,
-					inputParameters, outputData);
+					inputParameters, outputData, scope);
 
 			// print check on retrieving data
 			// logger.info("dbmanager-> output data retrieved");
@@ -1491,8 +1615,14 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 		if (isSessionExpired())
 			throw new SessionExpiredException();
 
-		try {
+		
 
+		try {
+			ASLSession session = SessionUtil.getAslSession(this
+					.getThreadLocalRequest().getSession());
+			// get scope
+			String scope = session.getScope();
+			
 			// data input
 			List<Parameter> inputParameters = new ArrayList<Parameter>();
 			// data ouptut
@@ -1531,7 +1661,7 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 			ComputationOutput outputData = new ComputationOutput();
 			// computation id
 			String computationId = startComputation(algorithmId,
-					inputParameters, outputData);
+					inputParameters, outputData, scope);
 
 			// print check on retrieving data
 			// logger.info("output data retrieved");
@@ -2033,14 +2163,15 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 	}
 
 	private String startComputation(String algorithmName,
-			List<Parameter> parameters, ComputationOutput outputData)
-			throws Exception {
-		return startComputation(algorithmName, parameters, outputData, null);
+			List<Parameter> parameters, ComputationOutput outputData,
+			String scope) throws Exception {
+		return startComputation(algorithmName, parameters, outputData, scope,
+				null);
 	}
 
 	private String startComputation(String algorithmName,
 			List<Parameter> parameters, ComputationOutput outputData,
-			String jobID) throws Exception {
+			String scopeValue, String jobID) throws Exception {
 
 		SMComputationConfig config = new SMComputationConfig();
 		SMInputEntry[] list = new SMInputEntry[parameters.size()];
@@ -2057,11 +2188,13 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 		request.config(config);
 
 		try {
-			StatisticalManagerFactory factory = getFactory();
+
+			StatisticalManagerFactory factory = getFactory(scopeValue);
 			String computationId = factory.executeComputation(request);
 
 			float percentage = 0;
-			String scope = getScope();
+			// String scope = getScope();
+			String scope = scopeValue;
 			String username = getUsername();
 
 			updateJobStatus(jobID, "computation started");
@@ -2231,9 +2364,9 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 		return u.openConnection().getInputStream();
 	}
 
-	private StatisticalManagerFactory getFactory() {
-		HttpSession httpSession = this.getThreadLocalRequest().getSession();
-		return SessionUtil.getFactory(httpSession);
+	private StatisticalManagerFactory getFactory(String scope) {
+		// HttpSession httpSession = this.getThreadLocalRequest().getSession();
+		return SessionUtil.getFactory(scope);
 	}
 
 	private String getUsername() {
@@ -2287,7 +2420,9 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 					}
 
 					if (computationId != null) {
-						StatisticalManagerFactory factory = getFactory();
+
+						// TODO ******* TO MODIFY
+						StatisticalManagerFactory factory = getFactory("");
 						try {
 							factory.removeComputation(computationId);
 							// remove submit query result
@@ -2347,12 +2482,20 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 	}
 
 	private synchronized void insertDataIntoCache(net.sf.ehcache.Element data) {
-		DBCache.put(data);
+		if (DBCache != null) {
+			DBCache.put(data);
+		}
 		// System.out.println("data inserted");
 	}
 
 	private synchronized net.sf.ehcache.Element getDataFromCache(String key) {
-		net.sf.ehcache.Element data = DBCache.get(key);
+		
+//		System.out.println("***get item with KEY: " + key);
+
+		net.sf.ehcache.Element data = null;
+		if (DBCache != null) {
+			data = DBCache.get(key);
+		}
 		return data;
 	}
 
@@ -2364,8 +2507,15 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 		// session check
 		if (isSessionExpired())
 			throw new SessionExpiredException();
+		
+		
 
 		try {
+			
+			ASLSession session = SessionUtil.getAslSession(this
+					.getThreadLocalRequest().getSession());
+			// get scope
+			String scope = session.getScope();
 
 			// // call the method related to the element selected
 			//
@@ -2374,6 +2524,7 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 
 			GeneralOutputFromServlet result = null;
 
+			//build key
 			if (inputData != null && inputData.size() != 0) {
 				// System.out.println("server-> input size not null");
 				String key = "";
@@ -2386,10 +2537,10 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 					// System.out.println("server-> element type not null");
 					switch (ElementType) {
 					case "listResources":
-						key = inputData.get("listResources");
+						key = scope+inputData.get("listResources");
 						break;
 					case "resource":
-						key = inputData.get("ResourceName");
+						key = scope+inputData.get("ResourceName");
 						break;
 					case "database":
 						if (element.getDatabaseType().equals(
@@ -2399,7 +2550,7 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 									+ inputData.get("DatabaseName");
 
 							// refresh submitted queries
-							keyUsedForQueryRefresh = ConstantsPortlet.ALGID_SUBMITQUERY
+							keyUsedForQueryRefresh = scope+ConstantsPortlet.ALGID_SUBMITQUERY
 									+ key;
 
 							refreshSubmittedQueryInCache(keyUsedForQueryRefresh);
@@ -2411,14 +2562,16 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 									+ inputData.get("DatabaseName")
 									+ inputData.get("SchemaName");
 
-							keyUsedForQueryRefresh = ConstantsPortlet.ALGID_SUBMITQUERY
+							keyUsedForQueryRefresh = scope+ConstantsPortlet.ALGID_SUBMITQUERY
 									+ key;
 							refreshSubmittedQueryInCache(keyUsedForQueryRefresh);
 
-							keyUsedForSamplingsRefresh = ConstantsPortlet.ALGID_SAMPLEONTABLE
+							keyUsedForSamplingsRefresh = scope+ConstantsPortlet.ALGID_SAMPLEONTABLE
 									+ key;
-							keyUsedForSmartSamplingRefresh = ConstantsPortlet.ALGID_SMARTSAMPLEONTABLE
+							keyUsedForSmartSamplingRefresh = scope+ConstantsPortlet.ALGID_SMARTSAMPLEONTABLE
 									+ key;
+							
+							key = scope + key;
 
 							refreshSamplingsInCache(keyUsedForSamplingsRefresh,
 									keyUsedForSmartSamplingRefresh);
@@ -2426,24 +2579,26 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 						break;
 
 					case "schema":
-						
+
 						key = inputData.get("ResourceName")
 								+ inputData.get("DatabaseName")
 								+ inputData.get("SchemaName");
 
-						// refresh submitted query and samplings
-						keyUsedForQueryRefresh = ConstantsPortlet.ALGID_SUBMITQUERY
+						// refresh submitted query and samplings and tables list
+						keyUsedForQueryRefresh = scope+ConstantsPortlet.ALGID_SUBMITQUERY
 								+ inputData.get("ResourceName")
 								+ inputData.get("DatabaseName");
 						refreshSubmittedQueryInCache(keyUsedForQueryRefresh);
-						keyUsedForSamplingsRefresh = ConstantsPortlet.ALGID_SAMPLEONTABLE
+						keyUsedForSamplingsRefresh = scope+ConstantsPortlet.ALGID_SAMPLEONTABLE
 								+ key;
-						keyUsedForSmartSamplingRefresh = ConstantsPortlet.ALGID_SMARTSAMPLEONTABLE
+						keyUsedForSmartSamplingRefresh = scope+ConstantsPortlet.ALGID_SMARTSAMPLEONTABLE
 								+ key;
+						
+						key = scope+key;
 
 						refreshSamplingsInCache(keyUsedForSamplingsRefresh,
 								keyUsedForSmartSamplingRefresh);
-
+						
 						break;
 					}
 				}
@@ -2560,9 +2715,9 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 		}
 		// remove keys
 		DBCache.removeAll(keysToBeRemoved);
-//		System.out.println("Samplings refreshed with keys: "
-//				+ keyUsedForSamplingsRefresh + " "
-//				+ keyUsedForSmartSamplingRefresh);
+		// System.out.println("Samplings refreshed with keys: "
+		// + keyUsedForSamplingsRefresh + " "
+		// + keyUsedForSmartSamplingRefresh);
 	}
 
 	private String storeResultIntoCSVFile(List<Result> result, String n)
@@ -2627,4 +2782,631 @@ public class GWTdbManagerServiceImpl extends RemoteServiceServlet implements
 		return queryParsed;
 	}
 
+	private synchronized void setEndThreadvariable() {
+		endThread = true;
+		logger.info("dbmanager-> variable EndThread set in order to stop the thread execution");
+
+	}
+
+	private synchronized boolean getEndThreadvariable() {
+		return endThread;
+	}
+
+	private List<FileModel> recoverResources(String scope) throws Exception {
+
+		try {
+
+			// initialize variables with application startup
+			// initVariables();
+
+			// data input
+			List<Parameter> inputParameters = new ArrayList<Parameter>();
+			// data output
+			List<FileModel> outputParameters = new ArrayList<FileModel>();
+
+			// get algorithmId
+			String algorithmId = ConstantsPortlet.ALGID_GETRESOURCE;
+
+			Parameter maxNumber = new Parameter("MaxNumber", "", "String", "-1");
+			inputParameters.add(maxNumber);
+
+			// check if the value is in cache. If data does not exist in cache
+			// the computation is started otherwise data are retrieved from
+			// cache.
+
+			// get data from cache
+			// check if data exist considering as key the input parameters
+			// String key = inputParameters.get(0).getDefaultValue();
+			String key = scope+"listResources";
+
+//			System.out.println("***GetResource KEY: " + key);
+			net.sf.ehcache.Element dataFromCache = getDataFromCache(key);
+
+			Object value = null;
+			if (dataFromCache != null) {
+				value = dataFromCache.getObjectValue();
+				// System.out.println("***GETTING DATA FROM CACHE");
+			}
+			if (value != null) {
+//				System.out.println("***GETTING DATA FROM CACHE");
+				outputParameters = (List<FileModel>) value;
+			} else {
+
+				// start the computation
+				// System.out.println("***STARTING THE COMPUTATION");
+				// create data structure for data output
+				ComputationOutput outputData = new ComputationOutput();
+				// computationId
+				String computationId = startComputation(algorithmId,
+						inputParameters, outputData, scope);
+
+				// print check
+				// retrieve data
+				// logger.info("output data retrieved");
+
+				// data output
+				LinkedHashMap<String, String> mapValues = new LinkedHashMap<String, String>();
+				mapValues = outputData.getMapValues();
+
+				for (int i = 0; i < mapValues.size(); i++) {
+					FileModel obj = new FileModel(mapValues.get(String
+							.valueOf(i)));
+					// obj.setIsLoaded(true);
+					outputParameters.add(obj);
+				}
+
+				if (outputParameters != null && outputParameters.size() != 0) {
+					// put data in cache
+					net.sf.ehcache.Element dataToCache = new net.sf.ehcache.Element(
+							key, outputParameters);
+
+					insertDataIntoCache(dataToCache);
+				}
+			}
+
+			return outputParameters;
+
+		} catch (Exception e) {
+			// e.printStackTrace();
+			// throw new Exception("Failed to load data. " + e);
+			logger.error("dbmanager-> ", e);
+			if (!(e instanceof StatisticalManagerException)) {
+				// GWT can't serialize all exceptions
+				throw new Exception(
+						"Error in server while loading data. Exception: " + e);
+			}
+			throw e;
+		}
+	}
+
+	private LinkedHashMap<String, FileModel> recoverDatabases(String scope,
+			String resourceName) throws Exception {
+		try {
+			// data input
+			List<Parameter> inputParameters = new ArrayList<Parameter>();
+			// data output
+			LinkedHashMap<String, FileModel> outputParameters = new LinkedHashMap<String, FileModel>();
+
+			String algorithmId = ConstantsPortlet.ALGID_GETDBINFO;
+
+			// print check
+			logger.info("dbmanager-> ResourceName: " + resourceName);
+
+			if ((resourceName == null) || (resourceName.equals(""))) {
+				throw new Exception("Unable to load data");
+			}
+
+			Parameter resource = new Parameter("ResourceName", "", "String", "");
+			inputParameters.add(resource);
+			inputParameters.get(0).setValue(resourceName);
+
+			// get data from cache
+			// check if data exist considering as key the input parameters
+			String key = scope+inputParameters.get(0).getValue();
+
+			// System.out.println("***KEY: " + key);
+			net.sf.ehcache.Element dataFromCache = getDataFromCache(key);
+
+			Object value = null;
+			if (dataFromCache != null) {
+				value = dataFromCache.getObjectValue();
+			}
+			if (value != null) {
+				outputParameters = (LinkedHashMap<String, FileModel>) value;
+				// System.out.println("***GETTING DATA FROM CACHE");
+			} else {
+
+				// start the computation
+				// System.out.println("***STARTING THE COMPUTATION");
+				// create data structure
+				ComputationOutput outputData = new ComputationOutput();
+				// computation id
+				String computationId = startComputation(algorithmId,
+						inputParameters, outputData, scope);
+
+				// print check
+				// retrieve data
+				// logger.info("output data retrieved");
+
+				// data output values
+				LinkedHashMap<String, String> mapValues = new LinkedHashMap<String, String>();
+				// data output keys
+				LinkedHashMap<String, String> mapKeys = new LinkedHashMap<String, String>();
+
+				mapValues = outputData.getMapValues();
+				mapKeys = outputData.getmapKeys();
+
+				for (int i = 0; i < mapValues.size(); i++) {
+					FileModel obj = new FileModel(mapValues.get(String
+							.valueOf(i)));
+					// obj.setIsLoaded(true);
+
+					// print check
+					// logger.info("value: " +
+					// mapValues.get(String.valueOf(i)));
+					// logger.info("key: " +
+					// mapKeys.get(String.valueOf(i)));
+					outputParameters.put(mapKeys.get(String.valueOf(i)), obj);
+				}
+
+				// write data in cache
+				if (outputParameters != null && outputParameters.size() != 0) {
+					// put data in cache
+//					net.sf.ehcache.Element dataToCache = new net.sf.ehcache.Element(
+//							inputParameters.get(0).getValue(), outputParameters);
+					net.sf.ehcache.Element dataToCache = new net.sf.ehcache.Element(
+							key, outputParameters);
+
+					insertDataIntoCache(dataToCache);
+				}
+			}
+
+			return outputParameters;
+
+		} catch (Exception e) {
+			// e.printStackTrace();
+			// throw new Exception("Failed to load data " + );
+			logger.error("dbmanager-> ", e);
+
+			if (!(e instanceof StatisticalManagerException)) {
+				// GWT can't serialize all exceptions
+				throw new Exception(
+						"Error in server while loading data. Exception: " + e);
+			}
+			throw e;
+		}
+	}
+
+	private List<FileModel> recoverSchema(String scope,
+			LinkedHashMap<String, String> dataInput) throws Exception {
+
+		try {
+
+			// data input
+			List<Parameter> inputParameters = new ArrayList<Parameter>();
+			// data output
+			List<FileModel> outputParameters = new ArrayList<FileModel>();
+
+			String algorithmId = ConstantsPortlet.ALGID_GETDBSCHEMA;
+			// print check
+			String rs = dataInput.get("ResourceName");
+			String db = dataInput.get("DatabaseName");
+
+			logger.info("dbmanager-> ResourceName: " + rs);
+			logger.info("dbmanager-> DatabaseName: " + db);
+
+			if ((rs == null) || (rs.equals(""))) {
+				throw new Exception("Unable to load data");
+			}
+			if ((db == null) || (db.equals(""))) {
+				throw new Exception("Unable to load data");
+			}
+
+			// set input parameters
+			Parameter resource = new Parameter("ResourceName", "", "String", "");
+			Parameter database = new Parameter("DatabaseName", "", "String", "");
+			inputParameters.add(resource);
+			inputParameters.add(database);
+
+			inputParameters.get(0).setValue(rs);
+			inputParameters.get(1).setValue(db);
+
+			// print check algorithm input parameters
+			// for (int i = 0; i < inputParameters.size(); i++) {
+			// logger.info(inputParameters.get(i).getName());
+			// }
+
+			// get data from cache
+			// check if data exist considering as key the input parameters
+			String key = scope+inputParameters.get(0).getValue()
+					+ inputParameters.get(1).getValue();
+
+			// System.out.println("key in GETSCHEMA: " + key);
+			net.sf.ehcache.Element dataFromCache = getDataFromCache(key);
+
+			Object value = null;
+			if (dataFromCache != null) {
+				value = dataFromCache.getObjectValue();
+			}
+			if (value != null) {
+				outputParameters = (List<FileModel>) value;
+			} else {
+
+				// start the computation
+				// create data structure
+				ComputationOutput outputData = new ComputationOutput();
+				// computation id
+				String computationId = startComputation(algorithmId,
+						inputParameters, outputData, scope);
+
+				// print check
+				// retrieve data
+				// logger.info("dbmanager-> output data retrieved");
+
+				// data output values
+				LinkedHashMap<String, String> mapValues = new LinkedHashMap<String, String>();
+				// data output keys
+				LinkedHashMap<String, String> mapKeys = new LinkedHashMap<String, String>();
+
+				mapValues = outputData.getMapValues();
+				mapKeys = outputData.getmapKeys();
+
+				for (int i = 0; i < mapValues.size(); i++) {
+					FileModel obj = new FileModel(mapValues.get(String
+							.valueOf(i)));
+					// obj.setIsSchema(true);
+					// obj.setIsLoaded(true);
+					outputParameters.add(obj);
+				}
+
+				// write data in cache
+				if (outputParameters != null && outputParameters.size() != 0) {
+					// put data in cache
+//					net.sf.ehcache.Element dataToCache = new net.sf.ehcache.Element(
+//							inputParameters.get(0).getValue()
+//									+ inputParameters.get(1).getValue(),
+//							outputParameters);
+					
+					net.sf.ehcache.Element dataToCache = new net.sf.ehcache.Element(
+							key,outputParameters);
+
+					insertDataIntoCache(dataToCache);
+					// DBCache.put(dataToCache);
+				}
+			}
+
+			return outputParameters;
+
+		} catch (Exception e) {
+			// e.printStackTrace();
+			// throw new Exception("Failed to load data. " + e);
+			logger.error("dbmanager-> ", e);
+			if (!(e instanceof StatisticalManagerException)) {
+				// GWT can't serialize all exceptions
+				throw new Exception(
+						"Error in server while loading data. Exception: " + e);
+			}
+			throw e;
+		}
+
+	}
+
+	private List<Result> recoverTables(String scope,
+			LinkedHashMap<String, String> dataInput, String elementType)
+			throws Exception {
+		try {
+
+			// data input
+			List<Parameter> inputParameters = new ArrayList<Parameter>();
+			// data output
+			List<Result> outputParameters = new ArrayList<Result>();
+
+			String algorithmId = ConstantsPortlet.ALGID_GETTABLES;
+
+			String rs = dataInput.get("ResourceName");
+			String db = dataInput.get("DatabaseName");
+			String scm = dataInput.get("SchemaName");
+
+			// print check
+			logger.info("dbmanager-> ResourceName: " + rs);
+			logger.info("dbmanager-> DatabaseName: " + db);
+			logger.info("dbmanager-> SchemaName: " + scm);
+
+			if ((elementType != null)
+					&& (elementType.equals(ConstantsPortlet.SCHEMA))) {
+				if ((rs == null) || (rs.equals(""))) {
+					throw new Exception("Unable to load data");
+				}
+				if ((db == null) || (db.equals(""))) {
+					throw new Exception("Unable to load data");
+				}
+				if ((scm == null) || (scm.equals(""))) {
+					throw new Exception("Unable to load data");
+				}
+			}
+			if ((elementType != null)
+					&& (elementType.equals(ConstantsPortlet.DATABASE))) {
+				if ((rs == null) || (rs.equals(""))) {
+					throw new Exception("Unable to load data");
+				}
+				if ((db == null) || (db.equals(""))) {
+					throw new Exception("Unable to load data");
+				}
+			}
+
+			// set input parameters
+			Parameter resource = new Parameter("ResourceName", "", "String", "");
+			Parameter database = new Parameter("DatabaseName", "", "String", "");
+			Parameter schema = new Parameter("SchemaName", "", "String", "");
+			inputParameters.add(resource);
+			inputParameters.add(database);
+			inputParameters.add(schema);
+
+			inputParameters.get(0).setValue(rs);
+			inputParameters.get(1).setValue(db);
+			inputParameters.get(2).setValue(scm);
+
+			// get data from cache
+			// check if data exist considering as key the input parameters
+			String key = scope+inputParameters.get(0).getValue()
+					+ inputParameters.get(1).getValue()
+					+ inputParameters.get(2).getValue();
+
+			// System.out.println("***KEY: " + key);
+			net.sf.ehcache.Element dataFromCache = getDataFromCache(key);
+
+			Object value = null;
+			if (dataFromCache != null) {
+				value = dataFromCache.getObjectValue();
+				// System.out.println("***GETTING DATA FROM CACHE");
+			}
+			if (value != null) {
+				outputParameters = (List<Result>) value;
+
+			} else {
+
+				// start computation
+				// create data structure
+				ComputationOutput outputData = new ComputationOutput();
+				// computation id
+				String computationId = startComputation(algorithmId,
+						inputParameters, outputData, scope);
+
+				// print check on retrieving data
+				// logger.info("output data retrieved");
+
+				// data output values
+				LinkedHashMap<String, String> mapValues = new LinkedHashMap<String, String>();
+				// data output keys
+				LinkedHashMap<String, String> mapKeys = new LinkedHashMap<String, String>();
+
+				mapValues = outputData.getMapValues();
+				mapKeys = outputData.getmapKeys();
+
+				for (int i = 0; i < mapValues.size(); i++) {
+					Result row = new Result(String.valueOf(i),
+							mapValues.get(String.valueOf(i)));
+					outputParameters.add(row);
+				}
+
+				// write data in cache
+				if (outputParameters != null && outputParameters.size() != 0) {
+					// put data in cache
+//					net.sf.ehcache.Element dataToCache = new net.sf.ehcache.Element(
+//							inputParameters.get(0).getValue()
+//									+ inputParameters.get(1).getValue()
+//									+ inputParameters.get(2).getValue(),
+//							outputParameters);
+					net.sf.ehcache.Element dataToCache = new net.sf.ehcache.Element(
+							key, outputParameters);
+
+					insertDataIntoCache(dataToCache);
+				}
+
+			}
+			return outputParameters;
+
+		} catch (Exception e) {
+			// e.printStackTrace();
+			// throw new Exception("Failed to load data. " + e);
+			// logger.error("dbmanager-> ", e);
+
+			if (!(e instanceof StatisticalManagerException)) {
+				// GWT can't serialize all exceptions
+				throw new Exception(
+						"Error in server while loading data. Exception: " + e);
+			}
+			throw e;
+		}
+
+	}
+
+	private synchronized void updateThreadsStarted(String scope, Boolean value) {
+		threadsStarted.put(scope, value);
+	}
+
+	private synchronized Boolean getThreadStarted(String scope) {
+		Boolean value = threadsStarted.get(scope);
+		return value;
+	}
+
+	// thread that loads data on the resources
+	private class ThreadLoaderData implements Runnable {
+		private String scope;
+
+		public ThreadLoaderData(String s) {
+			scope = s;
+		}
+
+		@Override
+		public void run() {
+			try {
+
+				// add an element related to the thread
+				updateThreadsStarted(scope, true);
+
+				if (!getEndThreadvariable()) {
+					List<FileModel> resources = recoverResources(scope);
+
+					int i = 0;
+					while ((!getEndThreadvariable()) && (i < resources.size())) {
+						getDatabase(resources.get(i).getName());
+						i++;
+						logger.error("dbmanager-> ***inside the while");
+					}
+
+					logger.error("dbmanager-> ***outside the while");
+				}
+				
+				logger.info("dbmanager-> ***Thread execution terminated");
+
+				// List<FileModel> resources = recoverResources(scope);
+				//
+				// for (int i = 0; i < resources.size(); i++) {
+				// getDatabase(resources.get(i).getName());
+				// }
+
+			} catch (Exception e) {
+				logger.error("dbmanager-> ", e);
+			}
+
+		}
+
+		private void getDatabase(String resourceName) {
+
+			try {
+
+				LinkedHashMap<String, FileModel> DBdata = recoverDatabases(
+						scope, resourceName);
+				if (DBdata != null) {
+					Set<String> keys = DBdata.keySet();
+					Object[] array = keys.toArray();
+
+					int numIterations = (DBdata.size()) / 5;
+					int i = 0;
+					int j = 0;
+					for (i = 0; i < numIterations; i++) {
+						// for (i = 0; i < 1; i++) {
+
+						// String DBName = "";
+						// for (j = (i * 5); j < (i + 1) * 5; j++) {
+						String DBName = "";
+						j = (i * 5);
+						while ((!getEndThreadvariable()) && (j < ((i + 1) * 5))) {
+
+							if (array[j].toString().contains("Database Name")) {
+								DBName = DBdata.get(array[j].toString())
+										.getName();
+							}
+
+							if (array[j].toString().contains("Driver Name")) {
+								String driver = DBdata.get(array[j].toString())
+										.getName();
+
+								if (driver.toUpperCase().contains(
+										ConstantsPortlet.POSTGRES)) {
+									// get schema
+									List<FileModel> schemaList = getSchema(
+											resourceName, DBName);
+									// recover tables
+									if (schemaList != null) {
+										int z = 0;
+										while ((!getEndThreadvariable())
+												&& (z < schemaList.size())) {
+											// for (int i = 0; i <
+											// schemaList.size(); i++) {
+											String schemaName = schemaList.get(
+													z).getName();
+//											System.out.println("SchemaName: "
+//													+ schemaName);
+
+											// LinkedHashMap<String, String>
+											// dataInputForTables = new
+											// LinkedHashMap<String, String>();
+											// dataInputForTables.put("ResourceName",
+											// resourceName);
+											// dataInputForTables.put("DatabaseName",
+											// DBName);
+											// dataInputForTables.put("SchemaName",
+											// schemaName);
+											getTables(resourceName, DBName,
+													schemaName,
+													ConstantsPortlet.SCHEMA);
+											z++;
+										}
+									}
+
+								}
+
+								if (driver.toUpperCase().contains(
+										ConstantsPortlet.MYSQL)) {
+									// get tables
+									getTables(resourceName, DBName, "",
+											ConstantsPortlet.DATABASE);
+								}
+							}
+							j++;
+						}
+					}
+				}
+			} catch (Exception e) {
+				logger.error("dbmanager-> ", e);
+			}
+		}
+
+		public List<FileModel> getSchema(String resourceName,
+				String databaseName) {
+
+			List<FileModel> schemaList = null;
+			try {
+
+				LinkedHashMap<String, String> dataInputForSchema = new LinkedHashMap<String, String>();
+				dataInputForSchema.put("ResourceName", resourceName);
+				dataInputForSchema.put("DatabaseName", databaseName);
+
+				schemaList = recoverSchema(scope, dataInputForSchema);
+
+				// if (schemaList != null) {
+				// int i=0;
+				// while((!getEndThreadvariable())&&( i < schemaList.size())){
+				// // for (int i = 0; i < schemaList.size(); i++) {
+				// String schemaName = schemaList.get(i).getName();
+				// System.out.println("SchemaName: " + schemaName);
+				//
+				// LinkedHashMap<String, String> dataInputForTables = new
+				// LinkedHashMap<String, String>();
+				// dataInputForTables.put("ResourceName", resourceName);
+				// dataInputForTables.put("DatabaseName", databaseName);
+				// dataInputForTables.put("SchemaName", schemaName);
+				// recoverTables(scope, dataInputForTables,
+				// ConstantsPortlet.SCHEMA);
+				// i++;
+				// }
+				// }
+
+			} catch (Exception e) {
+				logger.error("dbmanager-> ", e);
+			}
+			return schemaList;
+		}
+
+		public void getTables(String resourceName, String databaseName,
+				String schemaName, String elementType) {
+			try {
+
+				LinkedHashMap<String, String> dataInputForTables = new LinkedHashMap<String, String>();
+				dataInputForTables.put("ResourceName", resourceName);
+				dataInputForTables.put("DatabaseName", databaseName);
+				dataInputForTables.put("SchemaName", schemaName);
+
+				recoverTables(scope, dataInputForTables,
+						ConstantsPortlet.DATABASE);
+			} catch (Exception e) {
+				logger.error("dbmanager-> ", e);
+			}
+
+		}
+
+	}
+
 }