* src/ejabberd_auth.erl: Added get_vh_registered_users_number/1

function
* src/ejabberd_auth_odbc.erl: Likewise
* src/odbc/odbc_queries.erl: Added users_number/1 function
* src/ejabberd.cfg.example: Added an example for
pgsql_users_number_estimate option

SVN Revision: 766

ChangeLog

@@ -1,5 +1,12 @@
 2007-05-12  Alexey Shchepin  <alexey@sevcom.net>
 
+	* src/ejabberd_auth.erl: Added get_vh_registered_users_number/1
+	function
+	* src/ejabberd_auth_odbc.erl: Likewise
+	* src/odbc/odbc_queries.erl: Added users_number/1 function
+	* src/ejabberd.cfg.example: Added an example for
+	pgsql_users_number_estimate option
+
 	* src/ejabberd_auth_anonymous.erl: Added anonymous_purge_hook
 	(thanks to Christophe Romain and Mickael Remond)
 	* src/mod_offline.erl: Likewise

src/ejabberd.cfg.example

@@ -96,6 +96,10 @@
 %{auth_method, odbc}.
 %{odbc_server, "DSN=ejabberd;UID=ejabberd;PWD=ejabberd"}.
 
+% Uncomment this if you are using postgres, having a large DB, and need a
+% faster but inexact replacement for "select count(*) from users"
+%{pgsql_users_number_estimate, true}.
+
 
 % Host name:
 {hosts, ["localhost"]}.

src/ejabberd_auth.erl

@@ -22,6 +22,7 @@
 	 try_register/3,
 	 dirty_get_registered_users/0,
 	 get_vh_registered_users/1,
+	 get_vh_registered_users_number/1,
 	 get_password/2,
 	 get_password_s/2,
 	 is_user_exists/2,
@@ -107,6 +108,19 @@ get_vh_registered_users(Server) ->
 	      M:get_vh_registered_users(Server)
       end, auth_modules(Server)).
 
+get_vh_registered_users_number(Server) ->
+    lists:sum(
+      lists:map(
+	fun(M) ->
+		case erlang:function_exported(
+		       M, get_vh_registered_users_number, 1) of
+		    true ->
+			M:get_vh_registered_users_number(Server);
+		    false ->
+			length(M:get_vh_registered_users(Server))
+		end
+	end, auth_modules(Server))).
+
 get_password(User, Server) ->
     lists:foldl(
       fun(M, false) ->

src/ejabberd_auth_odbc.erl

@@ -18,6 +18,7 @@
 	 try_register/3,
 	 dirty_get_registered_users/0,
 	 get_vh_registered_users/1,
+	 get_vh_registered_users_number/1,
 	 get_password/2,
 	 get_password_s/2,
 	 is_user_exists/2,
@@ -28,8 +29,6 @@
 
 -include("ejabberd.hrl").
 
--record(passwd, {user, password}).
-
 %%%----------------------------------------------------------------------
 %%% API
 %%%----------------------------------------------------------------------
@@ -123,6 +122,15 @@ get_vh_registered_users(Server) ->
 	    []
     end.
 
+get_vh_registered_users_number(Server) ->
+    LServer = jlib:nameprep(Server),
+    case catch odbc_queries:users_number(LServer) of
+	{selected, [_], [{Res}]} ->
+	    list_to_integer(Res);
+	_ ->
+	    0
+    end.
+
 get_password(User, Server) ->
     case jlib:nodeprep(User) of
 	error ->

src/odbc/odbc_queries.erl

@@ -15,6 +15,7 @@
 	 del_user/2,
 	 del_user_return_password/3,
 	 list_users/1,
+	 users_number/1,
 	 add_spool_sql/2,
 	 add_spool/2,
 	 get_and_del_spool_msg_t/2,
@@ -109,6 +110,20 @@ list_users(LServer) ->
       LServer,
       "select username from users").
 
+users_number(LServer) ->
+    case ejabberd_config:get_local_option(
+	   {pgsql_users_number_estimate, LServer}) of
+	true ->
+	    ejabberd_odbc:sql_query(
+	      LServer,
+	      "select reltuples from pg_class "
+	      "where oid = 'users'::regclass::oid");
+	_ ->
+	    ejabberd_odbc:sql_query(
+	      LServer,
+	      "select count(*) from users")
+    end.
+
 add_spool_sql(Username, XML) ->
     ["insert into spool(username, xml) "
      "values ('", Username, "', '",