diff --git a/src/main/java/org/gcube/dataaccess/databases/structure/PostgresTableStructure.java b/src/main/java/org/gcube/dataaccess/databases/structure/PostgresTableStructure.java
index ba99151..14910a8 100644
--- a/src/main/java/org/gcube/dataaccess/databases/structure/PostgresTableStructure.java
+++ b/src/main/java/org/gcube/dataaccess/databases/structure/PostgresTableStructure.java
@@ -60,7 +60,7 @@ public class PostgresTableStructure extends AbstractTableStructure {
 				Object[] resultArray = (Object[]) result;
 
 				// retrieve the column name
-				String columnname = ((String) resultArray[0]).toLowerCase();
+				String columnname = ((String) resultArray[0]);
 				if (columnname.equalsIgnoreCase("class"))
 					columnname = "classcolumn";