diff --git a/dhp-workflows/dhp-aggregation/pom.xml b/dhp-workflows/dhp-aggregation/pom.xml
index d031c0308e..d523945ea8 100644
--- a/dhp-workflows/dhp-aggregation/pom.xml
+++ b/dhp-workflows/dhp-aggregation/pom.xml
@@ -55,6 +55,12 @@
 			<groupId>org.mongodb</groupId>
 			<artifactId>mongo-java-driver</artifactId>
 		</dependency>
+		
+		<dependency>
+            <groupId>org.postgresql</groupId>
+            <artifactId>postgresql</artifactId>
+            <version>42.2.10</version>
+        </dependency>
 
         <dependency>
             <groupId>org.mockito</groupId>
diff --git a/dhp-workflows/dhp-aggregation/src/main/java/eu/dnetlib/dhp/migration/AbstractMigrationExecutor.java b/dhp-workflows/dhp-aggregation/src/main/java/eu/dnetlib/dhp/migration/AbstractMigrationExecutor.java
index 3897905110..bf877dcf35 100644
--- a/dhp-workflows/dhp-aggregation/src/main/java/eu/dnetlib/dhp/migration/AbstractMigrationExecutor.java
+++ b/dhp-workflows/dhp-aggregation/src/main/java/eu/dnetlib/dhp/migration/AbstractMigrationExecutor.java
@@ -10,6 +10,8 @@ import java.util.concurrent.atomic.AtomicInteger;
 import java.util.stream.Collectors;
 
 import org.apache.commons.lang3.StringUtils;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
@@ -42,7 +44,12 @@ public class AbstractMigrationExecutor implements Closeable {
 
 	private final SequenceFile.Writer writer;
 
+	private static final Log log = LogFactory.getLog(AbstractMigrationExecutor.class);
+
 	public AbstractMigrationExecutor(final String hdfsPath, final String hdfsNameNode, final String hdfsUser) throws Exception {
+
+		log.info(String.format("Creating SequenceFile Writer, hdfsPath=%s, nameNode=%s, user=%s", hdfsPath, hdfsNameNode, hdfsUser));
+
 		this.writer = SequenceFile.createWriter(getConf(hdfsNameNode, hdfsUser), SequenceFile.Writer.file(new Path(hdfsPath)), SequenceFile.Writer
 				.keyClass(IntWritable.class), SequenceFile.Writer.valueClass(Text.class));
 	}
diff --git a/dhp-workflows/dhp-aggregation/src/main/java/eu/dnetlib/dhp/migration/DbClient.java b/dhp-workflows/dhp-aggregation/src/main/java/eu/dnetlib/dhp/migration/DbClient.java
index e9fee63b9a..246dae4746 100644
--- a/dhp-workflows/dhp-aggregation/src/main/java/eu/dnetlib/dhp/migration/DbClient.java
+++ b/dhp-workflows/dhp-aggregation/src/main/java/eu/dnetlib/dhp/migration/DbClient.java
@@ -9,6 +9,7 @@ import java.sql.SQLException;
 import java.sql.Statement;
 import java.util.function.Consumer;
 
+import org.apache.commons.lang3.StringUtils;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 
@@ -22,7 +23,9 @@ public class DbClient implements Closeable {
 
 		try {
 			Class.forName("org.postgresql.Driver");
-			this.connection = DriverManager.getConnection(address, login, password);
+
+			this.connection =
+					StringUtils.isNoneBlank(login, password) ? DriverManager.getConnection(address, login, password) : DriverManager.getConnection(address);
 			this.connection.setAutoCommit(false);
 		} catch (final Exception e) {
 			log.error(e.getClass().getName() + ": " + e.getMessage());
@@ -34,7 +37,7 @@ public class DbClient implements Closeable {
 	public void processResults(final String sql, final Consumer<ResultSet> consumer) {
 
 		try (final Statement stmt = connection.createStatement()) {
-			try (final ResultSet rs = stmt.executeQuery("SELECT * FROM COMPANY;")) {
+			try (final ResultSet rs = stmt.executeQuery(sql)) {
 				while (rs.next()) {
 					consumer.accept(rs);
 				}
diff --git a/dhp-workflows/dhp-aggregation/src/main/resources/eu/dnetlib/dhp/migration/migrate_db_entities_parameters.json b/dhp-workflows/dhp-aggregation/src/main/resources/eu/dnetlib/dhp/migration/migrate_db_entities_parameters.json
index 861d297bae..5e9f378f55 100644
--- a/dhp-workflows/dhp-aggregation/src/main/resources/eu/dnetlib/dhp/migration/migrate_db_entities_parameters.json
+++ b/dhp-workflows/dhp-aggregation/src/main/resources/eu/dnetlib/dhp/migration/migrate_db_entities_parameters.json
@@ -27,12 +27,12 @@
 		"paramName": "dbuser",
 		"paramLongName": "postgresUser",
 		"paramDescription": "postgres user",
-		"paramRequired": true
+		"paramRequired": false
 	},
 	{
 		"paramName": "dbpasswd",
 		"paramLongName": "postgresPassword",
 		"paramDescription": "postgres password",
-		"paramRequired": true
+		"paramRequired": false
 	}
 ]
\ No newline at end of file