From 4098bc6af049344650d4a580eca0e1f514c9774b Mon Sep 17 00:00:00 2001
From: niamtokik <mathieu.kerjouan@steepath.eu>
Date: Sun, 5 Nov 2023 11:16:00 +0000
Subject: [PATCH] update

---
 apps/mnesia_debug/src/mnesia_debug.erl        |  3 +-
 apps/mnesia_debug/src/mnesia_debug_sup.erl    |  5 +-
 apps/mnesia_debug/src/mnesia_debug_table.erl  | 24 ++++++++
 .../README.md                                 | 56 +++++++++++++++++++
 4 files changed, 86 insertions(+), 2 deletions(-)
 create mode 100644 apps/mnesia_debug/src/mnesia_debug_table.erl

diff --git a/apps/mnesia_debug/src/mnesia_debug.erl b/apps/mnesia_debug/src/mnesia_debug.erl
index 4f6c92c..b1f16c9 100644
--- a/apps/mnesia_debug/src/mnesia_debug.erl
+++ b/apps/mnesia_debug/src/mnesia_debug.erl
@@ -349,7 +349,8 @@ lookup(TypeAlias, Table, Key) ->
 
 load_table(TypeAlias, Table, Reason, CsList) -> 
     ?LOG_DEBUG("~p",[{?MODULE, self(), load_table, [TypeAlias, Table, Reason, CsList]}]),
-    throw({todo, ?MODULE, load_table, [TypeAlias, Table, Reason, CsList]}).
+    % throw({todo, ?MODULE, load_table, [TypeAlias, Table, Reason, CsList]}).
+    ok.
 
 %%--------------------------------------------------------------------
 %% @doc
diff --git a/apps/mnesia_debug/src/mnesia_debug_sup.erl b/apps/mnesia_debug/src/mnesia_debug_sup.erl
index c08d945..ca272a6 100644
--- a/apps/mnesia_debug/src/mnesia_debug_sup.erl
+++ b/apps/mnesia_debug/src/mnesia_debug_sup.erl
@@ -15,5 +15,8 @@ init([]) ->
                 , intensity => 0
                 , period => 1
                 },
-    ChildSpecs = [],
+    ChildSpecs = [#{ id => mnesia_debug_table
+                   , start => {mnesia_debug_table, start_link, []}
+                   }
+                 ],
     {ok, {SupFlags, ChildSpecs}}.
diff --git a/apps/mnesia_debug/src/mnesia_debug_table.erl b/apps/mnesia_debug/src/mnesia_debug_table.erl
new file mode 100644
index 0000000..5726176
--- /dev/null
+++ b/apps/mnesia_debug/src/mnesia_debug_table.erl
@@ -0,0 +1,24 @@
+-module(mnesia_debug_table).
+-behavior(gen_server).
+-export([start_link/0]).
+-export([init/1]).
+-export([handle_info/2, handle_cast/2, handle_call/3]).
+-include_lib("kernel/include/logger.hrl").
+
+start_link() ->
+    gen_server:start_link({local, ?MODULE}, ?MODULE, [], [debug]).
+
+init(_) -> 
+    {ok, []}.
+
+handle_cast(Message, State) ->
+    ?LOG_DEBUG("~p", [{?MODULE, self(), handle_cast, [Message, State]}]),
+    {noreply, State}.
+
+handle_call(Message, From, State) ->
+    ?LOG_DEBUG("~p", [{?MODULE, self(), handle_call, [Message, From, State]}]),
+    {noreply, State}.
+    
+handle_info(Message, State) ->
+    ?LOG_DEBUG("~p", [{?MODULE, self(), handle_info, [Message, State]}]),
+    {noreply, State}.
diff --git a/notes/0001-creating-custom-mnesia-backends-from-scratch/README.md b/notes/0001-creating-custom-mnesia-backends-from-scratch/README.md
index 522336d..a630e3b 100644
--- a/notes/0001-creating-custom-mnesia-backends-from-scratch/README.md
+++ b/notes/0001-creating-custom-mnesia-backends-from-scratch/README.md
@@ -38,6 +38,8 @@ more when this one is coming directly from Datalog world.
 
 ## Mnesia Custom Backend Steps
 
+### Table Creation Process
+
  1. A schema can be created using `mnesia:create_schema/0`
  
 ```erlang
@@ -89,6 +91,60 @@ mnesia:create_table( my_table
  8. Mnesia will call then `CustomModule:check_definition/4` function
     callback and should check the properties of the table.
 
+ 9. Then `Module:create_table/3` is called
+
+ 10. `Module:semantics/2`
+
+ 11. `Module:load_table/4`
+
+### Read Operations 
+
+Those operations are not altering the database content.
+
+#### `mnesia:read/2`
+
+ 1. `Module:lookup/3`
+
+#### `mnesia:first/1`
+
+ 1. `Module:first/2`
+
+#### `mnesia:last/1`
+
+ 1. `Module:last/2`
+
+#### `mnesia:prev/2`
+
+ 1. `Module:prev/3`
+
+#### `mnesia:next/2`
+
+ 1. `Module:next/3`
+
+#### `mnesia:all_keys/1`
+
+ 1. `Module:fixtable/3`
+
+#### `mnesia:select/2`
+
+ 1. `Module:fixtable/3`
+
+### Write Operations 
+
+Those operations are modifying database's content by creating,
+updating or deleting one or more entries.
+
+#### `mnesia:write/1`
+
+ 1. `Module:validate_record/6`
+
+#### `mnesia:delete/1`
+
+ 1. `Module:delete/3`
+
+#### `mnesia:delete_object/1`
+
+ 1. `Module:load_table/3`
 
 ## Backend Definition and Interfaces