diff --git a/plugins/dbms/mssqlserver/connector.py b/plugins/dbms/mssqlserver/connector.py
index 0c9602b5a..53a09f569 100644
--- a/plugins/dbms/mssqlserver/connector.py
+++ b/plugins/dbms/mssqlserver/connector.py
@@ -56,20 +56,27 @@ class Connector(GenericConnector):
             return None
 
     def execute(self, query):
+        retVal = False
+
         try:
             self.cursor.execute(utf8encode(query))
+            retVal = True
         except (pymssql.OperationalError, pymssql.ProgrammingError), msg:
             logger.warn(msg)
         except pymssql.InternalError, msg:
             raise sqlmapConnectionException, msg
 
+        return retVal
+
     def select(self, query):
-        self.execute(query)
-        value = self.fetchall()
+        retVal = None
 
-        try:
-            self.connector.commit()
-        except pymssql.OperationalError:
-            pass
+        if self.execute(query):
+            retVal = self.fetchall()
 
-        return value
+            try:
+                self.connector.commit()
+            except pymssql.OperationalError:
+                pass
+
+        return retVal
diff --git a/plugins/dbms/mysql/connector.py b/plugins/dbms/mysql/connector.py
index c3082a2b6..5ee413288 100644
--- a/plugins/dbms/mysql/connector.py
+++ b/plugins/dbms/mysql/connector.py
@@ -51,8 +51,11 @@ class Connector(GenericConnector):
             return None
 
     def execute(self, query):
+        retVal = False
+
         try:
             self.cursor.execute(query)
+            retVal = True
         except (pymysql.OperationalError, pymysql.ProgrammingError), msg:
             logger.warn(msg[1])
         except pymysql.InternalError, msg:
@@ -60,6 +63,12 @@ class Connector(GenericConnector):
 
         self.connector.commit()
 
+        return retVal
+
     def select(self, query):
-        self.execute(query)
-        return self.fetchall()
+        retVal = None
+
+        if self.execute(query):
+            retVal = self.fetchall()
+
+        return retVal
diff --git a/plugins/dbms/oracle/connector.py b/plugins/dbms/oracle/connector.py
index 29e113341..b86c2002b 100644
--- a/plugins/dbms/oracle/connector.py
+++ b/plugins/dbms/oracle/connector.py
@@ -60,8 +60,11 @@ class Connector(GenericConnector):
             return None
 
     def execute(self, query):
+        retVal = False
+
         try:
             self.cursor.execute(utf8encode(query))
+            retVal = True
         except (cx_Oracle.DatabaseError), msg:
             logger.warn(msg)
         except cx_Oracle.InternalError, msg:
@@ -69,6 +72,12 @@ class Connector(GenericConnector):
 
         self.connector.commit()
 
+        return retVal
+
     def select(self, query):
-        self.execute(query)
-        return self.fetchall()
+        retVal = None
+
+        if self.execute(query):
+            retVal = self.fetchall()
+
+        return retVal
diff --git a/plugins/dbms/postgresql/connector.py b/plugins/dbms/postgresql/connector.py
index 2569c954e..942b13c01 100644
--- a/plugins/dbms/postgresql/connector.py
+++ b/plugins/dbms/postgresql/connector.py
@@ -55,8 +55,11 @@ class Connector(GenericConnector):
             return None
 
     def execute(self, query):
+        retVal = False
+
         try:
             self.cursor.execute(query)
+            retVal = True
         except (psycopg2.OperationalError, psycopg2.ProgrammingError), msg:
             logger.warn(msg)
         except psycopg2.InternalError, msg:
@@ -64,6 +67,12 @@ class Connector(GenericConnector):
 
         self.connector.commit()
 
+        return retVal
+
     def select(self, query):
-        self.execute(query)
-        return self.fetchall()
+        retVal = None
+
+        if self.execute(query):
+            retVal = self.fetchall()
+
+        return retVal