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Is there a way to compare two fields from different MongoDB Collections?

+2 votes
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Is there a way to compare two fields from different MongoDB Collections?

I have a 2 collections:
collection_1: { "english" : { "orth" : "africa", "pron" : "frik" }, "francais" : { "orth" : "afrique" } }
collection_2: { "form" : { "orth" : "afrique", "pron" : "afik" } "sense" : { "cit" : { "quote" : "africa" } }}

I would like to find all where "collection_1.english.orth" == "collection_2.form.orth" and copy/add "form.pron" from collection_2 into collection_1 under "francais.pron".

posted Jan 26, 2016 by anonymous

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1 Answer

0 votes

As we cannot perform join operations in mongodb as mysql but we can try by using php cursors
use
foreach($cursor_collection_1 as $value_1)
{
foreach($cursor_collection_2 as $value_2)
{
//do operations //

}
}
Recently I used this method in one of my mongodb operations.It works.

answer Jan 26, 2016 by Shivam Kumar Pandey
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