pymongo - MongoDB: Removing a field from ALL subdocuments in an array field -

-

i have thousands of documents in format:

{ "_id" : objectid("51e98d196b01c2085c72d731"), "messages" : [     {         "_id" : objectid("520167056b01c20bb9eee987"),         "id" : objectid("520167056b01c20bb9eee987"),      },     {         "_id" : objectid("520167056b01c20bb9eee988"),         "id" : objectid("520167056b01c20bb9eee988"),      },     {         "_id" : objectid("520167056b01c20bb9eee989"),         "id" : objectid("520167056b01c20bb9eee989"),     } ], }

i need remove duplicate "id" field. have tried:

db.forum_threads.update({}, {$unset: {"messages.$.id": 1}}, {multi: true});

this error getting:

cannot apply positional operator without corresponding query field containing array.

the reason you're getting error because don't have predicate in filter clause. can this:

mongos> db.test.update({"messages.id": {$exists: true}}, {$unset: {"messages.$.id":true}}, {multi:true})

and won't error - in fact 1 of documents have id attribute removed. problem positional operator matches first element of array matches predicate, doesn't match elements. bigger issue it's not possible update elements in array in mongodb (https://jira.mongodb.org/browse/server-1243).

you'll either need iterate through each element in array using numerical position ("messages.0.id", "messages.1.id", etc.) or can pull array application, loop through elements , update them, , save array out.

you can see jira ticket issue has been open quite awhile 10gen doesn't seem consider high priority.


Comments

Post a Comment

Popular posts from this blog

Line ending issue with Mercurial or Visual Studio -

-
i seem have strange issue caused either visual studio or mercurial. localised single project, i'm guessing in project configuration causing issue. at difficult specify point, when perform action in visual studio, update every line ending in given file, means when @ file in sourcetree, every line has changed. i can replicate using nuget add package dependency; packages.config entirely replaced. if commit changes, including line endings, later same issue occur. workaround have shelve changes , reapply them, whereupon lines written correctly. i'm not sure application blame here. did make mistake of allowing sourcetree change mercurial configuration, issue have fixed, i'm not sure if has persisted. i thought might issue mercurial.ini files or hgrcs don't seem contain untoward. here's mercurial.ini [ui] username = .... [auth] bb.prefix = https://bitbucket.org/ bb.username = .... bb.password = .... [extensions] mq = rebase = [web] allow_push = * push_s...
Read more

java - Jtable duplicate Rows -

-
Image
when add new rows in jtable duplicate rows many times this method update jtable public final void tableaucomande(){ ((defaulttablemodel)tabcommande.getmodel()).getdatavector().clear(); session s=hibernateutil.getsessionfactory().opensession(); criteria cr1= s.createcriteria(commande.class); list <commande> lcs=cr1.list() ; criteria cr2= s.createcriteria(lignecommande.class); list <lignecommande> lck=cr2.list() ; if(lcs.size()!=0 && lck.size()!=0) { (commande lc:lcs) { for(lignecommande lig:lck){ ((defaulttablemodel)tabcommande.getmodel()).addrow(new object[]{ lc.getid_cmd(),lc.getnumcmd(),lc.getdate_cmd(),lc.getclient().getnomprenom(), lig.getproduit().getlib_prd(),lig.getquantite(),lig.getproduit().getid_prd() }); } } // tabcommande.setrowselectioninterval(tabcommande.getrowcount()-1,tabcommande.getrowcount()-1); } } this code add add data rows displaye...
Read more

java - Run a .jar on Heroku -

-
i trying run .jar file on heroku, , can't find instructions anywhere on how this. have read wants me compile uploading heroku. possible, , if is, how this? if helps, trying run minecraft craftbukkit server, , don't have pom.xml file yet. you didn't provide details i'll try give , people reaches question way it. first of all, create heroku account , create heroku application (assumed have done that). second, need generate application jar , upload heroku. so, open terminal , install heroku cli (assuming unix terminal): $ sudo npm install -g heroku-cli you need have npm , nodejs installed, can check link: https://www.digitalocean.com/community/tutorials/how-to-install-node-js-on-ubuntu-16-04 once done that, can use npm update node version acceptable heroku-cli: $ sudo npm install -g n $ sudo n 7.10.0 and run: $ sudo npm install -g heroku-cli in order deploy jars, need install deploy plugin: $ sudo heroku plugins:install heroku-cli-deploy ...
Read more