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Questions - lookup

While doing aggregation in MongoDB in lookup pipeline the id field is not available to perform match

As mentioned I want to match tenant id while looking in the logs collection and I am aggregating over Tenants collection. But this gives logs as an empty array. But when I did hardcoded the tenant_id...
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shubham

database

mongodb

nosql

lookup

aggregation

Votes: 0

Answers: 1

Latest Answer

If you want to find all the logs where the tenant_id (in the log schema) equals the _id from the tenant collection you called the aggregation on, you can define this in the lookup itself. Example: con...
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Maximilian Dolbaum

Pandas value lookup but with duplicate values

I have a list of lists containing prices of items, the order in which these elements are in, also matter. I also have a dataframe with the items in these lists and their correlating prices. I'm trying...
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mcfadX

python

pandas

dataframe

numpy

lookup

Votes: 0

Answers: 2

Latest Answer

One way using itertools.product and chain: from itertools import product, chain prices = df.groupby("Price")["Item"].apply(list) list(chain.from_iterable(product(*prices.loc[c]) f...
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Chris

Difference between lookup and join in oracle data integrator

I have created the basic mapping in ODI but i dont understand difference beaten lookup and join.
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user17104035

oracle

join

lookup

oracle-data-integrator

Votes: 0

Answers: 1

Latest Answer

Lookup provides the solution with left outer join by default. Lookup provides the efficiency to retrieve respective columns. Whereas, join enables you to perform inner join, left outer join, right out...
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Jim Macaulay

Counting multiple fields of a document in each other document against different fields in the same collection

I have millions of documents like this : { "anId" : "xxxxx-yyyyy-zzzzzz" "field1": "value1", "field2" : [ {"field1": "valu...
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Marco

mongodb

mongodb-query

aggregation-framework

lookup

Votes: 0

Answers: 1

Latest Answer

At the end of the day you're performing 3 lookups for 50k documents, those are 150k queries ( each performing an index scan). This means there's not much you can do to improve performance, especially ...
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Tom Slabbaert

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