diff --git a/lib/controller/checks.py b/lib/controller/checks.py
index 5c241b8b2..b4df11117 100644
--- a/lib/controller/checks.py
+++ b/lib/controller/checks.py
@@ -106,6 +106,10 @@ def checkSqlInjection(place, parameter, value):
                         msg = "do you want to include all tests for '%s' " % _
                         msg += "extending provided level (%d) and risk (%s)? [Y/n]" % (conf.level, conf.risk)
                         kb.extendTests = [] if readInput(msg, default='Y').upper() != 'Y' else (Backend.getErrorParsedDBMSes() or [kb.heuristicDbms])
+            elif kb.extendTests is None:
+                msg = "do you want to include all tests for '%s' " % conf.dbms
+                msg += "extending provided level (%d) and risk (%s)? [Y/n]" % (conf.level, conf.risk)
+                kb.extendTests = [] if readInput(msg, default='Y').upper() != 'Y' else ([conf.dbms])
 
             title = test.title
             stype = test.stype
diff --git a/lib/core/option.py b/lib/core/option.py
index 9e9c94715..a9af310d4 100644
--- a/lib/core/option.py
+++ b/lib/core/option.py
@@ -93,38 +93,29 @@ from lib.core.exception import SqlmapUnsupportedDBMSException
 from lib.core.exception import SqlmapUserQuitException
 from lib.core.log import FORMATTER
 from lib.core.optiondict import optDict
-from lib.core.settings import ACCESS_ALIASES
 from lib.core.settings import BURP_REQUEST_REGEX
 from lib.core.settings import BURP_XML_HISTORY_REGEX
 from lib.core.settings import CODECS_LIST_PAGE
 from lib.core.settings import CRAWL_EXCLUDE_EXTENSIONS
 from lib.core.settings import CUSTOM_INJECTION_MARK_CHAR
-from lib.core.settings import DB2_ALIASES
+from lib.core.settings import DBMS_ALIASES
 from lib.core.settings import DEFAULT_PAGE_ENCODING
 from lib.core.settings import DEFAULT_TOR_HTTP_PORTS
 from lib.core.settings import DEFAULT_TOR_SOCKS_PORT
 from lib.core.settings import DUMMY_URL
-from lib.core.settings import FIREBIRD_ALIASES
 from lib.core.settings import INJECT_HERE_MARK
 from lib.core.settings import IS_WIN
 from lib.core.settings import KB_CHARS_BOUNDARY_CHAR
 from lib.core.settings import LOCALHOST
-from lib.core.settings import MAXDB_ALIASES
 from lib.core.settings import MAX_CONNECT_RETRIES
 from lib.core.settings import MAX_NUMBER_OF_THREADS
-from lib.core.settings import MSSQL_ALIASES
-from lib.core.settings import MYSQL_ALIASES
 from lib.core.settings import NULL
-from lib.core.settings import ORACLE_ALIASES
 from lib.core.settings import PARAMETER_SPLITTING_REGEX
-from lib.core.settings import PGSQL_ALIASES
 from lib.core.settings import PROBLEMATIC_CUSTOM_INJECTION_PATTERNS
 from lib.core.settings import SITE
-from lib.core.settings import SQLITE_ALIASES
 from lib.core.settings import SQLMAP_ENVIRONMENT_PREFIX
 from lib.core.settings import SUPPORTED_DBMS
 from lib.core.settings import SUPPORTED_OS
-from lib.core.settings import SYBASE_ALIASES
 from lib.core.settings import TIME_DELAY_CANDIDATES
 from lib.core.settings import UNION_CHAR_REGEX
 from lib.core.settings import UNKNOWN_DBMS_VERSION
@@ -890,11 +881,9 @@ def _setDBMS():
         errMsg += "it and sqlmap will fingerprint it for you."
         raise SqlmapUnsupportedDBMSException(errMsg)
 
-    for aliases in (MSSQL_ALIASES, MYSQL_ALIASES, PGSQL_ALIASES, ORACLE_ALIASES, \
-                    SQLITE_ALIASES, ACCESS_ALIASES, FIREBIRD_ALIASES, \
-                    MAXDB_ALIASES, SYBASE_ALIASES, DB2_ALIASES):
+    for dbms, aliases in DBMS_ALIASES:
         if conf.dbms in aliases:
-            conf.dbms = aliases[0]
+            conf.dbms = dbms
 
             break
 
diff --git a/lib/core/settings.py b/lib/core/settings.py
index 4f1e23616..4a3b8eb7a 100644
--- a/lib/core/settings.py
+++ b/lib/core/settings.py
@@ -201,6 +201,8 @@ DBMS_DIRECTORY_DICT = dict((getattr(DBMS, _), getattr(DBMS_DIRECTORY_NAME, _)) f
 SUPPORTED_DBMS = MSSQL_ALIASES + MYSQL_ALIASES + PGSQL_ALIASES + ORACLE_ALIASES + SQLITE_ALIASES + ACCESS_ALIASES + FIREBIRD_ALIASES + MAXDB_ALIASES + SYBASE_ALIASES + DB2_ALIASES + HSQLDB_ALIASES
 SUPPORTED_OS = ("linux", "windows")
 
+DBMS_ALIASES = ((DBMS.MSSQL, MSSQL_ALIASES), (DBMS.MYSQL, MYSQL_ALIASES), (DBMS.PGSQL, PGSQL_ALIASES), (DBMS.ORACLE, ORACLE_ALIASES), (DBMS.SQLITE, SQLITE_ALIASES), (DBMS.ACCESS, ACCESS_ALIASES), (DBMS.FIREBIRD, FIREBIRD_ALIASES), (DBMS.MAXDB, MAXDB_ALIASES), (DBMS.SYBASE, SYBASE_ALIASES), (DBMS.DB2, DB2_ALIASES))
+
 USER_AGENT_ALIASES = ("ua", "useragent", "user-agent")
 REFERER_ALIASES = ("ref", "referer", "referrer")
 HOST_ALIASES = ("host",)