diff --git a/README.md b/README.md
index 0c58c2b..2d9a1b6 100644
--- a/README.md
+++ b/README.md
@@ -71,12 +71,10 @@ Date: 19/06/2019
 
 Author: E. Pallier (epallier@irap.omp.eu)
 
-VERSION: 0.30.11
+VERSION: 0.30.12
 
 Comment :
-- Bugfixed AgentM
-- Named test database "test_pyros" explicitely
-- Keep test database test_pyros (do not delete it after tests)
+- "./pyros install -p -d" => (-p = packages_only ; -d = -database_only)
  
 
 	RAPPELS SUR L'UTILISATION :
@@ -114,6 +112,13 @@ Full list of commits: https://gitlab.irap.omp.eu/epallier/pyros/commits/master
 (The new official changes history is here :  https://tinyurl.com/pyros-dev#heading=h.2r55bflctpt5)
 
 
+**19/06/2019 : v0.30.11 (EP)**
+
+	- Bugfixed AgentM
+	- Named test database "test_pyros" explicitely
+	- Keep test database test_pyros (do not delete it after tests)
+
+
 **12/06-17/06/2019 : v0.30.3-9 (EP)**
 
 	- Restructuration du projet - phase 1 : /src/ => /pyros_django/
diff --git a/install/install.py b/install/install.py
index 0891682..006cb48 100755
--- a/install/install.py
+++ b/install/install.py
@@ -376,21 +376,28 @@ def install_database(venv):
 
 def _help():
     print(
-        "Welcome in the installation script of the pyros venv.\t\nPlease launch it from the install directory of pyros.\n\tIf you're on Ubuntu Debian or CentOS:\n\tlaunch it with sudo and <--prerequisites> or <-p> to install the prerequisites.\n\t-->sudo ./test_install.py -p\n\n\tFor the python packages launch it from the install directory of pyros without sudo and without parameter\n\t-->./test_install.py")
-
+        #"Welcome in the installation script of the pyros venv.\t\nPlease launch it from the install directory of pyros.\n\tIf you're on Ubuntu Debian or CentOS:\n\tlaunch it with sudo and <--prerequisites> or <-p> to install the prerequisites.\n\t-->sudo ./test_install.py -p\n\n\tFor the python packages launch it from the install directory of pyros without sudo and without parameter\n\t-->./test_install.py")
+        "Welcome to the installation script of the pyros software.\t\n" + \
+        "Usage:\n" + \
+        "  [python] ./pyros.py install [-p] [-d]"
+    )
 
 
 
 
 if __name__ == '__main__':
-    if (len(sys.argv) > 1):
+    if len(sys.argv) > 2: _help() ; sys.exit(1)
+    #print(sys.argv)
+    if len(sys.argv) == 2:
+        INSTALL_VENV = INSTALL_DB = False
+        if sys.argv[1] == '-p': INSTALL_VENV=True
+        if sys.argv[1] == '-d': INSTALL_DB=True
+        '''
+        # Prerequisistes installation (for CentOS) => not a good idea for now, deactivated (EP)
         if sys.argv[1] == "--prerequisites" or sys.argv[1] == "-p":
             install_required()
         else:
             _help()
-    elif len(sys.argv) == 1:
-        if INSTALL_VENV: install_venv(VENV)
-        if INSTALL_DB: install_database(VENV)
-
-    else:
-        _help()
+        '''
+    if INSTALL_VENV: install_venv(VENV)
+    if INSTALL_DB: install_database(VENV)
diff --git a/pyros.py b/pyros.py
index cf85a33..f3130b3 100755
--- a/pyros.py
+++ b/pyros.py
@@ -288,16 +288,23 @@ def dbshell():
 
 
 @pyros_launcher.command(help="Install the pyros software")
+@click.option('--packages_only', '-p', is_flag=True, help='install only the python packages (no database installation)')
+@click.option('--database_only', '-d', is_flag=True, help='install only the pyros database (no python packages installation)')
 #@global_test_options
-def install():
+def install(packages_only, database_only):
     print("Running install command")
+    print("packages_only", packages_only)
+    print("database_only", database_only)
     #if test_mode(): print("in test mode")
     # self.execProcess("python3 install/install.py install")
     # if (os.path.basename(os.getcwd()) != "private"):
     start_dir = os.getcwd()
     os.chdir("install/") ; _in_dir("install") or die("Bad dir")
     # execProcess("python install.py install")
-    if not test_mode(): execProcess(PYTHON + " install.py")
+    option=''
+    if packages_only: option='-p'
+    if database_only: option='-d'
+    test_mode() or execProcess(PYTHON + " install.py " + option)
     # cd -
     # os.chdir("-")
     os.chdir(start_dir) ; _in_abs_dir(start_dir) or die("Bad dir")
--
libgit2 0.21.2