diff --git a/src/main/java/com/alibaba/druid/sql/dialect/postgresql/parser/PGExprParser.java b/src/main/java/com/alibaba/druid/sql/dialect/postgresql/parser/PGExprParser.java
index 5a50b36e6f..82933ae544 100644
--- a/src/main/java/com/alibaba/druid/sql/dialect/postgresql/parser/PGExprParser.java
+++ b/src/main/java/com/alibaba/druid/sql/dialect/postgresql/parser/PGExprParser.java
@@ -30,6 +30,18 @@ public class PGExprParser extends SQLExprParser {
     public PGExprParser(Lexer lexer){
         super(lexer);
     }
+    
+    public boolean isAggreateFunction(String word) {
+        String[] aggregateFunctions = { "AVG", "COUNT", "MAX", "MIN", "STDDEV", "SUM", "ROW_NUMBER" };
+
+        for (int i = 0; i < aggregateFunctions.length; ++i) {
+            if (aggregateFunctions[i].compareToIgnoreCase(word) == 0) {
+                return true;
+            }
+        }
+
+        return false;
+    }
 
     @Override
     public PGOrderBy parseOrderBy() {
diff --git a/src/main/java/com/alibaba/druid/util/JdbcUtils.java b/src/main/java/com/alibaba/druid/util/JdbcUtils.java
index 8aa458ae1d..e8c9ecbea7 100644
--- a/src/main/java/com/alibaba/druid/util/JdbcUtils.java
+++ b/src/main/java/com/alibaba/druid/util/JdbcUtils.java
@@ -47,11 +47,9 @@ import com.alibaba.druid.support.logging.LogFactory;
  */
 public final class JdbcUtils implements JdbcConstants {
 
-    
+    private final static Log        LOG              = LogFactory.getLog(JdbcUtils.class);
 
-    private final static Log        LOG               = LogFactory.getLog(JdbcUtils.class);
-
-    private static final Properties driverUrlMapping  = new Properties();
+    private static final Properties driverUrlMapping = new Properties();
 
     static {
         try {
@@ -213,13 +211,21 @@ public final class JdbcUtils implements JdbcConstants {
                     } else {
                         out.print(String.valueOf(objec));
                     }
+                } else if (type == Types.NULL) {
+                    out.print("null");
                 } else {
                     Object objec = rs.getObject(columnIndex);
 
                     if (rs.wasNull()) {
                         out.print("null");
                     } else {
-                        out.print(String.valueOf(objec));
+                        if (objec instanceof byte[]) {
+                            byte[] bytes = (byte[]) objec;
+                            String text = HexBin.encode(bytes);
+                            out.print(text);
+                        } else {
+                            out.print(String.valueOf(objec));
+                        }
                     }
                 }
             }
@@ -462,7 +468,7 @@ public final class JdbcUtils implements JdbcConstants {
             return null;
         }
     }
-    
+
     public static Driver createDriver(String driverClassName) throws SQLException {
         return createDriver(null, driverClassName);
     }
@@ -479,7 +485,7 @@ public final class JdbcUtils implements JdbcConstants {
                 throw new SQLException(e.getMessage(), e);
             }
         }
-        
+
         try {
             return (Driver) Class.forName(driverClassName).newInstance();
         } catch (IllegalAccessException e) {