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I have a simple Query which is there to recommend Users under a Post related Posts.

await this.$fireStore.collection('posts')
.limit(6).where('tags', 'array-contains', this.post.tags[0]).get().then(querySnapshot => {

Problem is that this also Reads out the Post itself (since it contains the Tag too), is there any way to query for Posts that dont have a specific DocID without wasting a Where ergo needing a complete new Query?

niclas_4
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  • If I understands correctly that you would like to only read (fetch) a part of a document, this is not possible: with a query you will get the entire document. You may duplicate your data if, for example, the volume of one document is too important to be downloaded when you only need a small subset of its data. – Renaud Tarnec Dec 09 '18 at 09:48
  • @RenaudTarnec No this is completly not what I want, I wanna get documents except a document with a specific ID – niclas_4 Dec 09 '18 at 10:55
  • Ok, I understand! I've proposed an approach in my answer below. – Renaud Tarnec Dec 09 '18 at 11:18

1 Answers1

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Firestore doesn't provide the possibility to query with inequality (i.e. not equals), see for example this SO post: Firestore: how to perform a query with inequality / not equals

I understand that you want to get a maximum of 6 "sibling" posts. You could make the same query, with a limit of 7 docs and, in your front-end, filter the result:

By looping over the list of docs and compare their Id to the current doc Id you will encounter two cases:

  1. The current doc is within the 7 docs returned by the query: remove it from the list
  2. The current doc is NOT within the 7 docs returned by the query: remove one doc randomly.
Renaud Tarnec
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