Azure OpenAI vectorizer

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The Azure OpenAI vectorizer connects to a deployed embedding model on your Azure OpenAI resource to generate embeddings at query time. Your data is processed in the Geo where your model is deployed.

Vectorizers are used at query time, but specified in index definitions, and referenced on vector fields through a vector profile. The Azure OpenAI vectorizer is called AzureOpenAIVectorizer in the API.

Note

This vectorizer is bound to Azure OpenAI and is charged at the existing Azure OpenAI Standard Pay-in-Advance Offer price.

Prerequisites

Your Azure OpenAI Service must have an associated custom subdomain. If the service was created through the Azure portal, this subdomain is automatically generated as part of your service setup. Ensure that your service includes a custom subdomain before using it with the Azure AI Search integration.

Azure OpenAI Service resources (with access to embedding models) that were created in AI Studio aren't supported. Only the Azure OpenAI Service resources created in the Azure portal are compatible with the Azure OpenAI Embedding skill integration.

Vectorizer parameters

Parameters are case-sensitive.

Parameter name Description
resourceUri The URI of the model provider, in this case, an Azure OpenAI resource. This parameter only supports URLs with domain openai.azure.com, such as https://<resourcename>.openai.azure.com. If the Azure OpenAI endpoint has a URL with domain cognitiveservices.azure.com, like https://<resourcename>.cognitiveservices.azure.com, a custom subdomain with openai.azure.com must be created first for the Azure OpenAI resource and use https://<resourcename>.openai.azure.com instead.
apiKey The secret key used to access the model. If you provide a key, leave authIdentity empty. If you set both the apiKey and authIdentity, the apiKey is used on the connection.
deploymentId The name of the deployed Azure OpenAI embedding model. The model should be an embedding model, such as text-embedding-ada-002. See the List of Azure OpenAI models for supported models.
authIdentity A user-managed identity used by the search service for connecting to Azure OpenAI. You can use either a system or user managed identity. To use a system manged identity, leave apiKey and authIdentity blank. The system-managed identity is used automatically. A managed identity must have Cognitive Services OpenAI User permissions to send text to Azure OpenAI.
modelName (Required in API version 2024-05-01-Preview and later). The name of the Azure OpenAI embedding model that is deployed at the provided resourceUri and deploymentId. Currently supported values are text-embedding-ada-002, text-embedding-3-large, and text-embedding-3-small

Supported vector query types

The Azure OpenAI vectorizer only supports text vector queries.

Expected field dimensions

The expected field dimensions for a field configured with an Azure OpenAI vectorizer depend on the modelName that is configured.

modelName Minimum dimensions Maximum dimensions
text-embedding-ada-002 1536 1536
text-embedding-3-large 1 3072
text-embedding-3-small 1 1536

Sample definition

"vectorizers": [
    {
        "name": "my-openai-vectorizer",
        "kind": "azureOpenAI",
        "azureOpenAIParameters": {
            "resourceUri": "https://my-fake-azure-openai-resource.openai.azure.com",
            "apiKey": "0000000000000000000000000000000000000",
            "deploymentId": "my-ada-002-deployment",
            "authIdentity": null,
            "modelName": "text-embedding-ada-002",
        },
    }
]

See also