# Error when using relativeScoreFusion as fusion\_type in hybrid search

**URL:** <https://forum.weaviate.io/t/error-when-using-relativescorefusion-as-fusion-type-in-hybrid-search/1502>\
**Category:** Support\
**Created:** [February 16, 2024, 11:49am UTC](https://forum.weaviate.io/t/error-when-using-relativescorefusion-as-fusion-type-in-hybrid-search/1502 "2024-02-16T11:49:55Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![A\_S](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.weaviate.io/a_s/32/690_2.png) [@A\_S](https://forum.weaviate.io/u/A_S)\
**Post date:** [February 16, 2024, 11:49am UTC](https://forum.weaviate.io/t/error-when-using-relativescorefusion-as-fusion-type-in-hybrid-search/1502/1 "2024-02-16T11:49:55Z")

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I’m using hybrid search and trying to get the relativeScoreFusion. The line in question:

.with\_hybrid(query=query, alpha=0.5, vector=embedded\_query, fusion\_type=HybridFusion.RELATIVE\_SCORE)

Unfortunately whenever I look for matching chunks in Weaviate while using this search I run into the following error:

‘Argument “hybrid” has invalid value {query: “What is an elephant?”, vector: [_0.00557935…_], alpha: 0.5, fusionType: relativeScoreFusion}. In field “fusionType”: Unknown field.’, ‘path’: None}]}

I’m using weaviate-client version 3.23.2, which includes the functionality, if I’m not mistaken. Am I doing something wrong?

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**Author:** ![DudaNogueira](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.weaviate.io/dudanogueira/32/7846_2.png) [@DudaNogueira](https://forum.weaviate.io/u/DudaNogueira)\
**Post date:** [February 16, 2024, 1:00pm UTC](https://forum.weaviate.io/t/error-when-using-relativescorefusion-as-fusion-type-in-hybrid-search/1502/2 "2024-02-16T13:00:08Z")

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Hi!

I was not able to reproduce this. ☹

What version of the server are you running?

Here is a full python notebook I have crafted using latest versions:  
python client 4.4.4  
server version 1.23.9

> <https://gist.github.com/dudanogueira/9660de2f9bb68151afd741d3c4096b5e>

Let me know if this helps.

Thanks!

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<div class="post-metadata">

**Author:** ![A\_S](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.weaviate.io/a_s/32/690_2.png) [@A\_S](https://forum.weaviate.io/u/A_S)\
**Post date:** [February 16, 2024, 2:37pm UTC](https://forum.weaviate.io/t/error-when-using-relativescorefusion-as-fusion-type-in-hybrid-search/1502/3 "2024-02-16T14:37:55Z")

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Thank you for your quick response! The Notebook works… Then it could only be the server version 1.19.8 that is causing this issue?

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<div class="post-metadata">

**Author:** ![DudaNogueira](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.weaviate.io/dudanogueira/32/7846_2.png) [@DudaNogueira](https://forum.weaviate.io/u/DudaNogueira)\
**Post date:** [February 16, 2024, 8:25pm UTC](https://forum.weaviate.io/t/error-when-using-relativescorefusion-as-fusion-type-in-hybrid-search/1502/4 "2024-02-16T20:25:16Z")

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Most certain.

A lot have hapenned since this version. Well, to be fair, a lot is happening in each new version.

For example, 1.24 just entered at release candidate, bringing alog other new features and improvements, the much awaited **named vectors** :

> **[Release v1.24.0-rc.0 - High Frequency Updates, HNSW Binary Quantization,...](https://github.com/weaviate/weaviate/releases/tag/v1.24.0-rc.0)**
>
> This is a release candidate for the upcoming v1.24.0 release
> A release candidate (RC) means the release is considered feature complete and has finished beta-testing. Any issues discovered during th...

So I would suggest backing up your cluster and upgrading both the cluster and the client.

Note that, the pyhon client 4.4.4 has retrocompatibility with v3 code, so it should work fine.

However, we strongly suggest migrating your code to v4, as v3 will not receive new features and will only have security patchs for some time.

Let me know if this helps or if there is anything more I can do to help!

Thanks for using Weaviate 🤗