meh / amnesia Goto Github PK

== Compilation error in file lib/exquisite.ex ==
** (CompileError) lib/exquisite.ex:103: CALLER is available only inside defmacro and defmacrop
lib/exquisite.ex:103: (module)
could not compile dependency :exquisite, "mix compile" failed. You can recompile this dependency with "mix deps.compile exquisite", update it with "mix deps.update exquisite" or clean it with "mix deps.clean exquisite"

Elixir Version = Elixir v1.7.0-dev

Hi,

I am trying to create example application using Phoenix with Amnesia. But, having trouble creating the database using the mix task which fails with below error. I am not sure the docs that I found from blogs are up to date or I missed something.

mix amnesia.create -d Database --disk
** (Mix) could not load Database, error: :nofile. Please pass a proper database with the --database option.

mix --version
Erlang/OTP 20 [erts-9.2.1] [source] [64-bit] [smp:8:8] [ds:8:8:10] [async-threads:10] [hipe] [kernel-poll:false] [dtrace]

Mix 1.6.1 (compiled with OTP 20)

Example Git repo: https://github.com/ganimp84/amnesia_example

On Elixir 1.6.0, where statements with and or or operators cause compilation errors. The where macro works fine when they are not used, but when they are, for some reason elixir expands the match fields to functions (which don't exist), throwing a compilation error.

Environment Details:

• Elixir 1.6.0
• Erlang 20.1
• Amnesia 0.2.7 (Exquisite 0.1.7)
• MacOS High Sierra 10.13.2

Reproducing the Issue:

A simple elixir application with amnesia set up, along with this DB/Table. This would not compile on Elixir 1.6.0, but if you remove the find/2 method, it will.

use Amnesia

defdatabase DB do
  deftable Post, [:user, :status, :content] do

    # Insert a Post
    def insert(user, status, content) do
      Amnesia.transaction do
        write(%DB.Post{user: user, status: status, content: content})
      end
    end


    # Find all posts by user
    def find(p_user) do
      Amnesia.transaction do
        where(user == p_user)
        |> Amnesia.Selection.values
      end
    end


    # Find all posts by user and status
    def find(p_user, p_status) do
      Amnesia.transaction do
        where(user == p_user and status == p_status)
        |> Amnesia.Selection.values
      end
    end

  end
end

Error:

Erlang/OTP 20 [erts-9.1] [source] [64-bit] [smp:4:4] [ds:4:4:10] [async-threads:10] [hipe] [kernel-poll:false]

Compiling 1 file (.ex)
warning: variable "user" does not exist and is being expanded to "user()", please use parentheses to remove the ambiguity or change the variable name
  lib/amnesia.ex:26

warning: variable "status" does not exist and is being expanded to "status()", please use parentheses to remove the ambiguity or change the variable name
  lib/amnesia.ex:26


== Compilation error in file lib/amnesia.ex ==
** (CompileError) lib/amnesia.ex:26: undefined function status/0
    (stdlib) lists.erl:1338: :lists.foreach/2
    lib/amnesia.ex:4: (module)
    (elixir) lib/kernel/parallel_compiler.ex:198: anonymous fn/4 in Kernel.ParallelCompiler.spawn_workers/6

Everything else works as expected. This is a serious bug which also affects one of my projects; Que. Hoping this gets resolved soon!

For some reason delete does not actually delete a message. Here is a relevant test. You can skip first three lines related to phoenix, it is related to the code writing to amnesia.

test "server receives message, stores it and replies with `received` status", %{socket: socket, user: user, chat: chat} do
    {:ok, _, socket} = subscribe_and_join(socket, "chats:#{chat.id}", %{})
    ref = push socket, "message", %{body: "the body", client_id: 1, created_at: :os.system_time(:seconds)}
    assert_reply ref, :ok, %{client_id: 1, status: "received"}

    [message] = Amnesia.transaction do
      selection = Message.where chat_id == chat.id, select: [id, body, client_id, chat_id, created_at, status, user_id]
      selection
      |> Amnesia.Selection.values
    end
    chat_id = chat.id
    user_id = user.id
    assert [id, "the body", 1, ^chat_id, _, "received", ^user_id] = message

    # Trying to delete here
    status = Amnesia.transaction do
      IO.inspect Message.last
      Message.last |> Message.delete
    end

    IO.inspect status

    # receiving ** (MatchError) no match of right hand side value: [[1, "the body", 1, 293, 1465198234, "received", 1514]]
    [] = Amnesia.transaction do
      selection = Message.where chat_id == chat.id, select: [id, body, client_id, chat_id, created_at, status, user_id]
      selection
      |> Amnesia.Selection.values
    end
  end

In order to avoid having a dependency in master it would be nice to be able to anchor it to a release. Thanks! 😄

As far as I understand, if we want to run a function on each record on table (to filter, or map...), we could use the foldl/3 function.

But, it's hard to use, because the value passed to function isn't a struct, for example, if we have

defdatabase Database do
  deftable Account, [{:id, autoincrement}, :email, :account_number :amount],
  ...

and use

Amnesia.transaction do
  Database.Account.foldl([], &([&1 | &2]))
end

The return is something like [{Database.Account, 1, "[email protected]", "1", 100000, true}, {Database.Account, 2, "[email protected]", "2", 100000, true}].

A possible better return is [%Database.Account{account_number: "1", amount: 100000, email: "[email protected]", id: 1}, %Database.Account{account_number: "2", amount: 100000, email: "[email protected]", id: 2}].

Currently, I'm using a workaround to return an array of structs:

Amnesia.transaction do
  Database.Account.keys
  |> Enum.map(&Database.Account.read!/1)
end

But, maybe exists a better solution, and I think that it's useful to add on Amnesia.

I am using exrm to create my uat and production releases. They are created with all the compiled beams as well as the erts and tar'd and zipped into a standalone file that gets extracted on the target box. How am I supposed to create the initial mnesia db via amnesia (mix amnesia.create -db Database) on the target box?

Thanks

Geoff

I used this project in Elixir 0.14.1, and my module looks like:

defmodule Cc do
  use Amnesia

  defdatabase Database do
    deftable Job, [{:id, autoincrement}, :mod, :vnode, :queue, :status, :opts], type: :ordered_set do
    end

    deftable Hint, [{:id, autoincrement}, :vnode, :url], type: :set do
    end

    def start() do
      Amnesia.Schema.create

      # start mnesia
      Amnesia.start

      # create tables
      #Clear.Database.Job.create(disk: [node])
      #Clear.Database.Hint.create(disk: [node])
      Database.create(disk: [node])

      # This waits for the database to be fully created.
      Database.wait
    end

    def stop do
      Amnesia.stop
    end

  end
end

in iex, I start Amnesia, then I want to create a new column,

iex> Cc.Database.Job[mod: :mod1, vnode: 1, queue: nil, status: :new, opts: []]
** (Protocol.UndefinedError) protocol Access not implemented for Cc.Database.Job, only the nil atom is supported
    (elixir) lib/access.ex:144: Access.Atom.undefined/1

I think it results of the Record isn't belongs to Elixir Kernel anymore, could you fix it to adapt Elixir's Map struct？

If there weren't any results, it should return e.g. nil. Right now it does raise a Protocol.UndefinedError

I implemented a small testcase for this:
https://github.com/mweibel/amnesia_small_testcase

• clone
• mix compile
• mix installDb
• mix test

should be Keyword
https://github.com/meh/amnesia/blob/master/lib/amnesia/table.ex#L73

I tried to create table with

deftable Test, [:id, :content, :secondary_index],
                     type: :ordered_set,
                     index: [:secondary_index] do
...

then when i tried to read by index i get error

Test.read_at(index_value, :secondary_index)

{:no_exists, Database.Test, {:index, [3]}}

warning: function Amnesia.result/1 is undefined or private
Found at 7 locations:
lib/amnesia.ex:159
lib/amnesia.ex:168
lib/amnesia.ex:194
lib/amnesia.ex:204
lib/amnesia.ex:229
lib/amnesia.ex:255
lib/amnesia.ex:281

When I try to use example code in IEx

Amnesia.transaction do
john = %User{name: "John", email: "[email protected]"} |> User.write
end

error is raised.

** (UndefinedFunctionError) function :erl_eval.match1/4 is undefined or private
       (uym) User.write(%User{email: "[email protected]", id: nil, name: "John"})
    (stdlib) erl_eval.erl:670: :erl_eval.do_apply/6
    (stdlib) erl_eval.erl:438: :erl_eval.expr/5
    (mnesia) mnesia_tm.erl:835: :mnesia_tm.apply_fun/3
    (mnesia) mnesia_tm.erl:810: :mnesia_tm.execute_transaction/5

in lib/database.ex is example code from README. Database was created using

mix amnesia.create -db Database --disk

Content of database.ex

use Amnesia
defdatabase Database do
  deftable User

  deftable Message, [:user_id, :content], type: :bag do
    @type t :: %Message{user_id: integer, content: String.t}

    def user(self) do
      User.read(self.user_id)
    end

    def user!(self) do
      User.read!(self.user_id)
    end
  end

  deftable User, [{ :id, autoincrement }, :name, :email], type: :ordered_set, index: [:email] do
    @type t :: %User{id: non_neg_integer, name: String.t, email: String.t}

    def add_message(self, content) do
      %Message{user_id: self.id, content: content} |> Message.write
    end

    def add_message!(self, content) do
      %Message{user_id: self.id, content: content} |> Message.write!
    end

    def messages(self) do
      Message.read(self.id)
    end

    def messages!(self) do
      Message.read!(self.id)
    end
  end
end

defmodule User do
  defstruct id: nil, name: nil, email: nil
end

defmodule Message do
  defstruct user_id: nil, content: nil
end

I use Elixir 1.3.2, {:amnesia, "~> 0.2.4"}.

What could be wrong?

== Compilation error on file lib/amnesia/event.ex ==
** (CompileError) lib/amnesia/event.ex:29: type record() undefined
(stdlib) lists.erl:1337: :lists.foreach/2
(stdlib) erl_eval.erl:669: :erl_eval.do_apply/6

The defined table User is defined as an ordered_set. According to the OTP source code, :mnesia.dirty_update_counter does only work on tables/records defined as set.

Is this assumption correct?

Should be "0.0.2" for repository tag "v0.0.2". Otherwise the dependency given on http://expm.co results in the following error message:

Unchecked dependencies for environment dev:

• amnesia [git: "https://github.com/meh/amnesia.git"]
  the dependency does not match the specified version, got 0.0.1

Hi,

It doesnt compile on the last elixir ( 0.10.3 ) :(

mix deps.compile amnesia

• Compiling amnesia
  Compiled lib/amnesia/counter.ex
  == Compilation error on file lib/amnesia.ex ==
  could not compile dependency amnesia, mix compile failed. If you want to recompile this dependency, please run: mix deps.compile amnesia
  ** (CompileError) deps/amnesia/lib/amnesia.ex:66: function to_binary/1 undefined
  lists.erl:1323: :lists.foreach/2
  /private/tmp/elixir-1HDh/elixir-0.10.3/lib/elixir/lib/kernel/parallel_compiler.ex:82: Kernel.ParallelCompiler."-spawn_compilers/8-fun-0-"/3

Based on looking at the tests I wrote:

Amnesia.transation! do
Enum.each quotes, fn(q) ->
StockData.StockQuotes[symbol: q.symbol, date: q.date, open: q.open, high: q.high,
low: q.low, close: q.close, volume: q.volume, adjClose: q.adjClose].write
end
end

And it always fails with:

** (exit) {:aborted,:no_transaction}
mnesia.erl:309: :mnesia.abort/1
lists.erl:1313: :lists.foreach/2
/Users/gclements/work/elixir/lib/elixir/lib/enum.ex:284: Enum.each/2

Amnesia.start and StockData.StockQuotes.create both succeeded. What am I missing?

Hi,

I'm having an issue using the exquisite selector. I've written this code, from the README section:

    Amnesia.transaction do
      existing_user = User.where(email == new_mail, select: id) |> Amnesia.Selection.values
      existing_user
    end

My table user: deftable User, [ :id, :email, :name, :password ], type: :ordered_set, index: [:email]

At compilation time i'm getting this error:

== Compilation error on file lib/mnesia.ex ==
** (CompileError) lib/mnesia.ex:51: function email/0 undefined
    (stdlib) lists.erl:1336: :lists.foreach/2
    lib/mnesia.ex:31: (module)

What I am missing? Thanks!

Hi,

Attempting to create an app using the examples on the README, I get the following error:

** (CompileError) lib/test/connection_store.ex:67: User.struct/0 is undefined, cannot expand struct User
(elixir) src/elixir_map.erl:44: :elixir_map.translate_struct/4
(stdlib) lists.erl:1352: :lists.mapfoldl/3
(elixir) src/elixir_clauses.erl:36: :elixir_clauses.clause/7
(elixir) src/elixir_fn.erl:9: anonymous fn/3 in :elixir_fn.translate/3
(stdlib) lists.erl:1352: :lists.mapfoldl/3

Is Amnesia supported in Elixir 0.15.0?

Thanks

I'm having trouble compiling continuum with mix deps.compile (Elixir 0.12.4):

== Compilation error on file lib/date.ex ==
could not compile dependency continuum, mix compile failed. You can recompile this dependency with `mix deps.compile continuum` or update it with `mix deps.update continuum`
** (UndefinedFunctionError) undefined function: Timezone.__using__/1
    Timezone.__using__([])
    lib/date.ex:2: (module)
    (stdlib) erl_eval.erl:569: :erl_eval.do_apply/6
    (elixir) src/elixir.erl:140: :elixir.eval_forms/4

Strangely, compiling it independently works just fine. Any ideas?

In the documentation for deftable, :indices is listed as an option when a user wishes to add additional indexes. However, the correct atom should be :index. The example code has the correct atom but the documentation doesn't. At https://hexdocs.pm/amnesia/Amnesia.Database.html#deftable/4 the first option is listed below:

:indices specifies a list of additional indices to use instead of the first attribute.

I've just copied this from the readme and put it in lib/Database.ex:

use Amnesia

defdatabase Database do
  deftable User, [{ :id, autoincrement }, :name, :email], type: :ordered_set, index: [:email] do
    # again not needed, but nice to have
    @type t :: %User{id: non_neg_integer, name: String.t, email: String.t}
  end
end

Then I created the database and tried reading / writing to the database, but it keeps returning :badarg:

➜  my_app git:(master) ✗ mix amnesia.create -db Database
Compiling 1 file (.ex)

20:15:37.891 [info]  Application mnesia exited: :stopped
➜  my_app git:(master) ✗ iex -S mix
Erlang/OTP 19 [erts-8.1] [source] [64-bit] [smp:8:8] [async-threads:10] [hipe] [kernel-poll:false] [dtrace]

Interactive Elixir (1.3.4) - press Ctrl+C to exit (type h() ENTER for help)
iex(1)> use Amnesia
Amnesia.Helper
iex(2)> use Database
[Amnesia, Amnesia.Fragment, Exquisite, Database, Database.User, Database.User]
iex(3)> Amnesia.transaction do
...(3)> john = %User{name: "John", email: "[email protected]"} |> User.write
...(3)>
...(3)> end
:badarg
iex(4)> Amnesia.transaction do
...(4)> User.read(1)
...(4)> end
:badarg
iex(5)>

What am I doing wrong?

BTW I also posted this question on stackoverflow: http://stackoverflow.com/questions/40965818/elixir-amnesia-badarg-when-doing-anything-to-the-database

I'm trying to set the attributes of a table from a variable / module_attribute in the deftable macro, but it raises an exception instead.

use Amnesia

defdatabase MyApp.DB do
  @attrs [:id, :a, :b, :c]

  deftable SomeTable, @attrs, type: :bag do
  end 
end

I also tried using unquote(@attrs) since it's a macro but that doesn't work either. Is there some way I can get this to work? (This is just an example, the attributes need to be loaded from another module during compile-time).

This is the error I get:

Compiling 1 file (.ex)

== Compilation error on file lib/mnesia.ex ==
** (ArgumentError) argument error
    :erlang.length({:@, [line: 6], [{:attrs, [line: 6], nil}]})
    lib/amnesia/table/definition.ex:63: Amnesia.Table.Definition.define/4
    expanding macro: Amnesia.Database.deftable/4
    lib/db.ex:6: MyApp.DB (module)

Hi,

thanks a lot for your effort to update it to the latest elixir version.
Since updating however, I have the mentioned warning when trying to compile my table definitions.

A sample definition where this comes up is the following:

#...
deftable Client, [:ref, :user_id, :data, :is_admin], type: :set, index: [:user_id], copying: :memory do
#...

Do you have an idea why this warning shows up?

Is there any chance you would be considering changing the chosen license?

I work in a start up where we are adopting Elixir and would love to use this package, but I see two major problems:

1. Your license terms basically allow me to wholesale steal your code without giving you credit. Obviously I don't want to do this because it's not just a jerk move, I consider it bad open source form to not give credit to the guy who did all the heavy lifting.
2. We integrate with enterprise customers, and as much as I love the ideals behind the license, there's no way I can convince to my boss or our clients to adopt software filled with a bunch of f-bombs, no matter how awesome. As stupid a thing as this is to prevent the usage of awesome software, corporate attitudes can hurt adoption.

Any idea if this could be changed to an equally permissive license which also gives you more credit while not horrifying a bunch of stuffed shirts?

To avoid the need for multiple index rows it would be ideal to be able to perform partial pattern matching on tuples

e.g.

:mnesia.match_object({AMNESIA.TABLE, {:tuple, :encoded, :cartesian, :index, :_})

But handling this would either require writing custom exquisite queries (? maybe)

or abandoning Amnesia.

It should be possible to provide a sort of last resort filtering library such that

Amnesia.Fragment.transaction do
  Amnesia.wrapper do
    :mnesia.match_object({AMNESIA.TABLE, {:tuple, :encoded, :cartesian, :index, :_})
  end
end

where the wrapper logic determines if the inner term returns

{[values], continuation} (:mnesia.select) or [values] (:mnesia.match_object) or %end_of_table or RecordList

and populates the appropriate Amnesia.Table.Select{coerce: table_from_result, continuation: continuation_from_result, values: values_from_result} or appropriate error response.

Some sort of built in last resort macro or documentation for performing partial matches if possible directly using Amnesia/Exquisite would greatly improve the portability of Amnesia.

I'm happy to provide the code for such if the code maintainers have any guidelines, requirements for such a change, but I'd need guidance on any pure Amnesia solution here.

Just upgraded to elixir 1.1.1 did a mix deps.update amnesia and now I am seeing the following warning

==> exquisite
warning: the dependency :exquisite requires Elixir "~> 1.0.0-rc1" but you are running on v1.1.1

Everything is working, just though I would report this.

I think it would help a lot to have some default mix tasks like create|drop|migrate (same as those found in ecto for easier understanding). Your example of install/uninstall in the README is pretty much what everybody does when starting a project with amnesia INMHO.

We would only need to support something like:

mix amnesia.create --database MyDatabase (more options)

Options I can think of are:

• --no-schema: would not create the mnesia schema
• --disc: would create passing the option disc:[node()]
• --disc-only: same as above but with disc only on node
  ... and other mnesia options.

To support migrate we could have some behaviour that would export a migrate function and we would receive the user module implementing that function. Again, close to Ecto's idiom.

I was starting out a PR but thought that it would be better to ask for opinions first. What do you think @meh?

How can I start Amnesia in disk_only_mode ?

I tried:

Database.create disk!: [node]

with result:

Database creation failure: [error: {:bad_type, Database, :disc_only_copies, :"smalldev@MacBook-Air"}, error: {:bad_type, Database.User, :disc_only_copies, :"smalldev@MacBook-Air"}, error: {:bad_type, Database.History, :disc_only_copies, :"smalldev@MacBook-Air"}]

What i'm doing wrong?

Hi,

So, I use the install task to create a schema, but when I try to access the database, I get

** (exit) {:aborted, {:no_exists, [UserStore.User, #PID<0.395.0>]}}
     stacktrace:
       mnesia.erl:310: :mnesia.abort/1
       lib/amnesia/table.ex:484: Amnesia.Table.read!/2
       (app) lib/app/connection_store.ex:6: App.UserStore.User.read!/1
       (app) lib/app/connection_store.ex:73: App.ConnectionStore.lookup/1
       test/app_test.exs:6

My Schema is created with:

deftable User, 
    [:pid,:username,:bytes,:datetime], 
    type: :set, 
    index: [:username] do
    @type t :: %User{pid: pid, 
                           username: String.t, 
                           bytes: non_neg_integer, 
                           datetime: {{non_neg_integer, non_neg_integer, non_neg_integer}, {non_neg_integer, non_neg_integer, non_neg_integer}}}

On install, the necessary folders do get created.

Im getting this error when I try to include this lib as a dependency:

** (Mix) No package with the name amnesia in registry

Here is my markup:

defp deps do
[
{:amnesia, "~> 0.1.1"},
{:collector, in_umbrella: true}
]
end

What am I doing wrong or how should I include it in my project manually

When I run Amnesia.Table.transform/3 in the iex shell the update works fine. However when I put it into a Mix.Tasks module it doesn't. Any hints on using Amnesia.Table.transform/3 in a Task ?

The same issue occurs when I put a :mnesia.transform_table in the run/1 function of the Task.

Hello!

I'm trying to create bunch of tables at once with the following code:

use Amnesia

defdatabase Database do
  for name <- [:"Elixir.TestTable", :"Elixir.AnotherTestTable"] do
    deftable name, [{ :id, autoincrement }, :user_id], type: :set do
    end
  end
end

That gives me the following error:

== Compilation error on file web/models/database.ex ==
** (CompileError) web/models/database.ex:5: undefined function name/0
    (stdlib) lists.erl:1337: :lists.foreach/2
    web/models/database.ex:5: anonymous fn/2 in :elixir_compiler_2.__MODULE__/1
    (elixir) lib/enum.ex:1473: Enum."-reduce/3-lists^foldl/2-0-"/3
    web/models/database.ex:4: (module)
    (elixir) lib/kernel/parallel_compiler.ex:100: anonymous fn/4 in Kernel.ParallelCompiler.spawn_compilers/8

I noticed that this code, however, is compiled correctly:

defdatabase Database do
  for name <- [:"Elixir.TestTable", :"Elixir.AnotherTestTable"] do
    defmodule name, do: []
  end
end

Given that, I decided to ask that question in the Amnesia tracker, not in some general Elixir thread.

How do I do table definitions with dynamic names correctly?

Using Amnesia 0.2.5 with Elixir 1.4.2, I see a warning repeated 4 times for every line where the defdatabase macro is called during compilation (via mix compile, if that makes a difference). Luckily, it's reproducible by simply making a new test.ex file with the following contents:

use Amnesia

defdatabase Test do
end

Compiling the above will result in the following, repeated 4 times for every use of defdatabase in each file being compiled:

warning: variable "metadata" does not exist and is being expanded to "metadata()", please use parentheses to remove the ambiguity or change the variable name

I'm trying to create a table in an existing database using exrm's release tasks. How is everyone else doing this? I'm doing it the following way:

def create_table(production_node, database, table_name) do
  {:ok, _} = Application.ensure_all_started(:app)

  # create table
  table_name.create(disk: [production_node])

  IO.puts "Waiting"
  :ok = database.wait(15000)

  IO.puts "Done"
  :init.stop()
end

Could we perhaps put something like this in the readme? Assuming this is correct, should I send a PR?

# mix amnesia.drop -d Database
** (FunctionClauseError) no function clause matching in Mix.Amnesia.ensure_database_module/1
    lib/mix/mix_amnesia.ex:10: Mix.Amnesia.ensure_database_module(nil)
    lib/mix/amnesia.drop.ex:10: Mix.Tasks.Amnesia.Drop.run/1
    (mix) lib/mix/task.ex:296: Mix.Task.run_task/3
    (mix) lib/mix/cli.ex:58: Mix.CLI.run_task/2
    (elixir) lib/code.ex:363: Code.require_file/2

There's no error if I replace -d with --database. I'm using amnesia 0.2.5, mix 1.3.3.

Sorry, this is more of a question than an issue. How do you make a disk based database? The RAM based code works fine. I'd just like to persist data to disk.

I think it should be:

Stocks.StockData.create [{:disk, [node]}]
Stocks.StockData.wait

but it hangs forever in wait. Am I calling create wrong?

Hey,

I'm probably doing something wrong but after trying various times I can't get a working result.
I have various queries specified within the deftable block and they don't seem to run (I don't even get an error usually). Previously I worked around this issue using Exquisite directly but somehow this doesn't work anymore since the newest Elixir release.

Sample function:

deftable ClientStatus, [:user_id, :room_id, :status], type: :bag, copying: :disk do
    @type clientStatusTypes :: ClientStatus[user_id: String.t, room_id: binary, status: boolean]

    def is_user_admin?(id) do
        selector = where user_id == id and status == :admin,
                            select: status
        case selector do
            nil ->
                false
            _result ->
                true
        end
    end
end

Do you have an idea what might be wrong here? I also tried doing various other ways to achieve the same result but all of them don't work..

# Error on compilation: function status/0 undefined
selector = ClientStatus.where user_id == id and status == :admin,
                                select: status

selector = ClientStatus.where :user_id == id and :status == :admin,
                                select: :status
# etc.

Thanks,
Michael

I get this error with Elixir 0.14.3. Downgrading to 0.14.2 solves the issue.

= Compilation error on file lib/amnesia/metadata.ex ==
** (CompileError) lib/amnesia/metadata.ex:105: type t() undefined
    (stdlib) lists.erl:1336: :lists.foreach/2
    (stdlib) erl_eval.erl:657: :erl_eval.do_apply/6
    (elixir) src/elixir.erl:170: :elixir.erl_eval/3
    (elixir) src/elixir.erl:158: :elixir.eval_forms/4
    (elixir) src/elixir_lexical.erl:17: :elixir_lexical.run/2
    (elixir) src/elixir.erl:170: :elixir.erl_eval/3

Full configuration: Elixir 0.14.3 and Erlang R17.1 on MacOS X 10.9.4.

amnesia no longer compiles under v0.9.x of Elixir.

Enum.Iterable no longer exists in Elixir. It was removed in v0.9.0. It was replaced by Enumerable.

Also there are a few places where the code references List.Dict.keys. It should be Dict.keys.

But the most work is in Amnesia.Table.Iterator. It looks like iterate needs to be replaced with reduce.

When I do MyTableName.delete(MyTableName, "mykey") I get "** (CaseClauseError) no case clause matching: "mykey"". Am I passing the name parameter wrong? The documentation basically just says, "see mnesia:delete". The mnesia:delete documentation says to pass the name of the table, but that seems unnecessary, since I've already specified the table with MyTableName.delete(). I like your library (and it's license terms) and I'd like to use it, but I'm really stuck here.

I see that there are couple other issues with compiling amnesia, but none of them helped solve me my problem:

== Compilation error on file lib/amnesia/table.ex ==
could not compile dependency amnesia, mix compile failed. If you want to recompile this dependency, please run: mix deps.compile amnesia
** (SyntaxError) deps/amnesia/lib/amnesia/table.ex:1569: syntax error before: '{'

I would like to use Amnesia in my Dynamo app. Here's my dependencies description:

  defp deps do
    [ { :cowboy, github: "extend/cowboy" },
      { :dynamo, "0.1.0-dev", github: "elixir-lang/dynamo" },
      { :amnesia, "0.1.1", [ github: "meh/amnesia", tag: "v0.1.1" ] } ]
  end

I use Elixir v0.10.3.

Hi.

When inside a block like the following, how do I abort the ongoing transaction?

Amnesia.transaction do < reads, writes > end

When I called :mnesia.abort/1, the whole process died due to an uncaught exception. Same happened when I introduced some kind of matching error in a transaction.

How does it work? How can I abort a transaction in Amnesia?

Good day,

I am new to Elixir and erlang, I am now playing with amnesia in phoenix application. I am unsure how to setup testing environment in phoenix application with amnesia, so that it would be as smooth as with ecto (or at least close to). How do you usually go about setting things up in phoenix with amnesia?

Hey there,

Thanks for the wrapper. I'm having trouble following samples. I defined the Database module, then Install / Uninstall tasks and after compiling and running "iex -S mix install" I can see that it hangs on the Database.wait line infinitely.

Any ideas what to try or where to look for help are greatly appreciated!

I think you should sync the Elixir version with your own continuum.

I'm using backup commands to create a snapshot of my database.
To create a snapshot, I'm using this code:

Amnesia.Backup.checkpoint(%{
  name: 'backup',
  max: [Database.Account, Database.VerifyCode],
  override: true
})
Amnesia.Backup.start('backup', 'backup')

It's works, creating a file called backup. But, when I restore this snapshot using

Amnesia.Backup.restore('backup', nil)

The tables that has an autoincrement column get problem, because the restore command doesn't restore the counter.
For example, if I restore the Account table, I get 5 rows from backup file, then, if I to add a new record on this table, the new record will replace the first record (because will have the same id, 1, instead of the correct id, 5).

I require ets: compressed for a project, but am unable to specify mnesia storage_options using just amnesia to define and create tables. I sent a pull request that has my intermediate fix for passing in ets and dets storage options during table definition and table creation.