Azure AI Search global filter does not apply to vector queries, use filterOverride

Not specified by the original author.

TL;DR

For hybrid queries, pass filterOverride in the vector query when the filter must constrain vector results too; the top-level filter only covers the text side. Also set k to at least 50 when using the semantic ranker, since it returns fewer results from too-small input sets.

Steps

1. For hybrid queries, pass filterOverride in the vector query when the filter must constrain vector results too; the top-level filter only covers the text side. If results look unfiltered on the vector half, this is the first thing to check. Also set k to at least 50 when using the semantic ranker, since it returns fewer results from too-small input sets.

When to use

You are seeing this: If results look unfiltered on the vector half, this is the first thing to check. Use this skill when you run into "Azure AI Search global filter does not apply to vector queries, use filterOverride".

When not to use

If your error message or symptom does not match what is described above, this is probably not your fix. Search for your exact error text instead of forcing this one to fit.

Versions

No specific versions are mentioned in the source material, so treat the fix as generally applicable and check the examples against whatever you have installed.

Why this happens

The original report does not dig into a root cause. It documents the symptom and the fix that resolved it.

Edge cases

• Also set k to at least 50 when using the semantic ranker, since it returns fewer results from too-small input sets.

Source: Official docs mirror (hybrid search how-to): documents the gotcha that a global filter is not applied to vector queries in Azure AI Search. If you need filtering on the vector portion of a hybrid query, you must use filterOverride inside the vector query itself (preview). Agents that set only the top-level filter will see unfiltered vector results mixed in.

Verified resolution: For hybrid queries, pass filterOverride in the vector query when the filter must constrain vector results too; the top-level filter only covers the text side. If results look unfiltered on the vector half, this is the first thing to check. Also set k to at least 50 when using the semantic ranker, since it returns fewer results from too-small input sets.

Source URL: https://github.com/leahyra/azure-ai-docs/blob/HEAD/articles/search/hybrid-search-how-to-query.md