in reply to MongoDB Stored procedure from Dancer2

According to MongoDB::Tutorial, you are supposed to not pass in _id at all to have MongoDB issue the id. If you want to hand out ids from a specific sequence, I don't know how to do that though.

I don't find any mention of "stored procedure" in the MongoDB distribution. I don't know how the API, and the closest I found was some random blog post on how to call server-side Javascript from Python. Most likely you have to send the same/similar data structure to make MongoDB do your bidding from Perl.

Update: See below for the official documentation on how to create an autoincrement field with MongoDB.

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Re^2: MongoDB Stored procedure from Dancer2
by actarus2003 (Novice) on Mar 28, 2017 at 15:47 UTC
    Thanks for replay, yes i try to use the code mentioned in the example, because the javascript procedure are volatile (as disconnect they disappear and you need to insert again) i save them. problem is when you try to add a document as example say ({"_id"=> getNextSequence("comm-id") +,"year" => "2017"}) it work fine, getNexSequence javascript work fine. but if i call it from perl it is not recognized and executed, so id will be 'getNextSequence("comm-id")' string
[reply]

      All I can suggest is the perl equivalent of the getNextSequence function

      my $filter = {'_id' => 'userid'};
my $update = { '$inc' => { 'seq' => 1} };
my $col = $db->get_collection('counters');
$col->update($filter,$update);
my $id = $col->find_one($filter)->{'seq'};
print $id;

      [download]

      You can probably use find_one_and_update() but it didn't work on my old version 0.45 of MongoDB

      poj
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[d/l]
[select]

        Poj,

        your suggestion is the right way, i will start from here.

        I Just underline update is deprecated

        @4000000058db6ef81e84eb6c # *** DEPRECATION WARNING ***
@4000000058db6ef81e84eb6c #
@4000000058db6ef81e84eb6c # The 'update' method will be removed in a f
+uture major release.
@4000000058db6ef81e84ef54 # Use $_, $_ or 'replace_one' instead.

        [download]

        so i made a little modification

            my $col = $db->get_collection('counters');
    $col->update_one({'_id' => 'comm-id'},{ '$inc' => { 'seq' => 1}});
    my $id = $col->find_one({'_id' => 'comm-id'})->{'seq'};

        [download]

        so now it is working.

        Thanks so much, it really help!

[reply]
[d/l]
[select]

      The example seems to send raw Javascript instead of JSON or BSON.

      I don't find any example in the MongoDB documentation that shows how to send raw Javascript.

[reply]

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