Moralis Query similar as Group By

Moralis General
#1

Hello!

How can I query a table grouping by a unique value? I want to do something like (in relational db)

Select (field) from (table) group by (field).

To be more specific, I want to query BscTokenBalance and retrieve all registered tokens, but I want to receive only one item for each token. I tried

const query = new Moralis.Query("BscTokenBalance")
query.select("symbol");
query.distinct("symbol");
const resposta = await query.find();

But they donā€™t group with this query. Thx in advance!

#2

you can search on how to do it with mongo db, also on how to do it with parse server, it may include a pipeline.

#3

Thanks, Iā€™ll look for how to do this in mongo, but then I didnā€™t understand this distinct method. Could someone give an example of use? From the example in the documentation, I didnā€™t understand very well.

#4

query.distinct may work only with master key, you could test it if it works

all it should to would be to keep only distinct entries, no group by

#5

Okay, thanks, I think I understand now. About the original question, itā€™s easy to do using pipeline. I come from a background in SQL databases, I need to get used to noSql. Iā€™ll post the solution because maybe it will help someone at some point.

const query = new Moralis.Query(ā€œBscTokenBalanceā€)
query.select(ā€œsymbolā€);
const pipeline = [{
group: {
objectId: ā€œ$symbolā€
}
}];
const resposta = await query.aggregate(pipeline);

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