mnesia_registry

1998 2013 Ericsson AB, All Rights Reserved The contents of this file are subject to the Erlang Public License, Version 1.1, (the "License"); you may not use this file except in compliance with the License. You should have received a copy of the Erlang Public License along with this software. If not, it can be retrieved online at http://www.erlang.org/. Software distributed under the License is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for the specific language governing rights and limitations under the License. The Initial Developer of the Original Code is Ericsson AB. mnesia_registry Dan Gudmundsson and Håkan Mattsson 98-04-24 A mnesia_registry.sgml

mnesia_registry Dump support for registries in erl_interface.

The module mnesia_registry is usually part of erl_interface, but for the time being, it is a part of the Mnesia application.

mnesia_registry is mainly an module intended for internal usage within OTP, but it has two functions that are exported for public use.

On C-nodes erl_interface has support for registry tables. These reside in RAM on the C-node but they may also be dumped into Mnesia tables. By default, the dumping of registry tables via erl_interface causes a corresponding Mnesia table to be created with mnesia_registry:create_table/1 if necessary.

The tables that are created with these functions can be administered as all other Mnesia tables. They may be included in backups or replicas may be added etc. The tables are in fact normal Mnesia tables owned by the user of the corresponding erl_interface registries.

create_table(Tab) -> ok | exit(Reason) Creates a registry table in Mnesia.

This is a wrapper function for mnesia:create_table/2 which creates a table (if there is no existing table) with an appropriate set of attributes. The table will only reside on the local node and its storage type will be the same as the schema table on the local node, ie. {ram_copies,[node()]} or {disc_copies,[node()]}.

It is this function that is used by erl_interface to create the Mnesia table if it did not already exist.

create_table(Tab, TabDef) -> ok | exit(Reason) Creates a customized registry table in Mnesia.

This is a wrapper function for mnesia:create_table/2 which creates a table (if there is no existing table) with an appropriate set of attributes. The attributes and TabDef are forwarded to mnesia:create_table/2. For example, if the table should reside as disc_only_copies on all nodes a call would look like:


          TabDef = [{{disc_only_copies, node()|nodes()]}],
          mnesia_registry:create_table(my_reg, TabDef)