Integrate Azure AI capabilities into Azure Database for PostgreSQL - Flexible Server

APPLIES TO: Azure Database for PostgreSQL - Flexible Server

The azure_ai extension adds the ability to use large language models (LLMs) and build generative AI applications within an Azure Database for PostgreSQL flexible server database by integrating the power of Azure AI services. Generative AI is a form of artificial intelligence in which LLMs are trained to generate original content based on natural language input. Using the azure_ai extension allows you to use generative AI's natural language query processing capabilities directly from the database.

This tutorial showcases adding rich AI capabilities to an Azure Database for PostgreSQL flexible server instance using the azure_ai extension. It covers integrating both Azure OpenAI and the Azure AI Language service into your database using the extension.

Prerequisites

• An Azure subscription - Create one for free.

• Access granted to Azure OpenAI in the desired Azure subscription. Currently, access to this service is granted by the application. You can apply for access to Azure OpenAI by completing the form at https://aka.ms/oai/access.

• An Azure OpenAI resource with the text-embedding-ada-002 (Version 2) model deployed. This model is currently only available in certain regions. If you don't have a resource, the process for creating one is documented in the Azure OpenAI resource deployment guide.

• An Azure AI Language service. If you don't have a resource, you can create a Language resource in the Azure portal by following the instructions provided in the quickstart for summarization document. You can use the free pricing tier (Free F0) to try the service and upgrade later to a paid tier for production.

• An Azure Database for PostgreSQL flexible server instance in your Azure subscription. If you don't have a resource, use either the Azure portal or the Azure CLI guide for creating one.

Connect to the database using psql in the Azure Cloud Shell

Open the Azure Cloud Shell in a web browser. Select Bash as the environment and, if prompted, select the subscription you used for your Azure Database for PostgreSQL flexible server database, then select Create storage.

To retrieve the database connection details:

1. Navigate to your Azure Database for PostgreSQL flexible server resource in the Azure portal.

2. From the left-hand navigation menu, select Connect under Settings and copy the Connection details block.

3. Paste the copied environment variable declaration lines into the Azure Cloud Shell terminal you opened above, replacing the {your-password} token with the password you set when creating the database.

   export PGHOST={your-server-name}.postgresql.database.azure.com
   export PGUSER={your-user-name}
   export PGPORT=5432
   export PGDATABASE={your-database-name}
   export PGPASSWORD="{your-password}"
   

   Connect to your database using the psql command-line utility by entering the following at the prompt.

   psql
   

Install the azure_ai extension

Azure AI extension and OpenAI

The azure_ai extension allows you to integrate Azure OpenAI and Azure Cognitive Services into your database. To enable the extension in your database, follow the steps below:

1. Add the extension to your allowlist as described in Extensions - Azure Database for PostgreSQL - Flexible Server.

2. Verify that the extension was successfully added to the allowlist by running the following from the psql command prompt:

   SHOW azure.extensions;
   

3. In the database in which you plan to use the azure_ai extension, install it by using the CREATE EXTENSION command.

   CREATE EXTENSION azure_ai;
   

Inspect the objects contained within the azure_ai extension

Reviewing the objects contained within the azure_ai extension can provide a better understanding of the capabilities it offers. You can use the \dx meta-command from the psql command prompt to list the objects contained within the extension.

\dx+ azure_ai

The meta-command output shows that the azure_ai extension creates three schemas, multiple user-defined functions (UDFs), and several composite types in the database. The table below lists the schemas added by the extension and describes each.

The functions and types are all associated with one of the schemas. To review the functions defined in the azure_ai schema, use the \df meta-command, specifying the schema whose functions should be displayed. The \x auto commands before the \df command toggle the expanded display on and off automatically to make the output from the command easier to view in the Azure Cloud Shell.

\x auto
\df+ azure_ai.*

The azure_ai.set_setting() function lets you set the endpoint and critical values for Azure AI services. It accepts a key and the value to assign it. The azure_ai.get_setting() function provides a way to retrieve the values you set with the set_setting() function. It accepts the key of the setting you want to view. For both methods, the key must be one of the following:

Generate vector embeddings with Azure OpenAI

The azure_ai extension's azure_openai schema enables the use of Azure OpenAI for creating vector embeddings for text values. Using this schema, you can generate embeddings with Azure OpenAI directly from the database to create vector representations of input text, which can then be used in vector similarity searches, and consumed by machine learning models.

Embeddings are a technique of using machine learning models to evaluate how closely related information is. This technique allows for efficient identification of relationships and similarities between data, allowing algorithms to identify patterns and make accurate predictions.

Set the Azure OpenAI endpoint and key

Before using the azure_openai functions:

1. Configure the extension with your Azure OpenAI service endpoint and key.

2. Navigate to your Azure OpenAI resource in the Azure portal and select the Keys and Endpoint item under Resource Management from the left-hand menu.

3. Copy your endpoint and access key. You can use either KEY1 or KEY2. Always having two keys allows you to securely rotate and regenerate keys without causing service disruption.

In the command below, replace the {endpoint} and {api-key} tokens with values you retrieved from the Azure portal, then run the commands from the psql command prompt to add your values to the configuration table.

SELECT azure_ai.set_setting('azure_openai.endpoint','{endpoint}');
SELECT azure_ai.set_setting('azure_openai.subscription_key', '{api-key}');

Verify the settings written in the configuration table:

SELECT azure_ai.get_setting('azure_openai.endpoint');
SELECT azure_ai.get_setting('azure_openai.subscription_key');

The azure_ai extension is now connected to your Azure OpenAI account and ready to generate vector embeddings.

Populate the database with sample data

This tutorial uses a small subset of the BillSum dataset, which provides a list of United States Congressional and California state bills, to provide sample text data for generating vectors. The bill_sum_data.csv file containing these data can be downloaded from the Azure Samples GitHub repo.

To host the sample data in the database, create a table named bill_summaries.

CREATE TABLE bill_summaries
(
    id bigint PRIMARY KEY,
    bill_id text,
    bill_text text,
    summary text,
    title text,
    text_len bigint,
    sum_len bigint
);

Using the PostgreSQL COPY command from the psql command prompt, load the sample data from the CSV into the bill_summaries table, specifying that the first row of the CSV file is a header row.

\COPY bill_summaries (id, bill_id, bill_text, summary, title, text_len, sum_len) FROM PROGRAM 'curl "https://raw.githubusercontent.com/Azure-Samples/Azure-OpenAI-Docs-Samples/main/Samples/Tutorials/Embeddings/data/bill_sum_data.csv"' WITH CSV HEADER ENCODING 'UTF8'

Enable vector support

The azure_ai extension allows you to generate embeddings for input text. To enable the generated vectors to be stored alongside the rest of your data in the database, you must install the pgvector extension by following the guidance in the enable vector support in your database documentation.

With vector supported added to your database, add a new column to the bill_summaries table using the vector data type to store embeddings within the table. The text-embedding-ada-002 model produces vectors with 1536 dimensions, so you must specify 1536 as the vector size.

ALTER TABLE bill_summaries
ADD COLUMN bill_vector vector(1536);

Generate and store vectors

The bill_summaries table is now ready to store embeddings. Using the azure_openai.create_embeddings() function, you create vectors for the bill_text field and insert them into the newly created bill_vector column in the bill_summaries table.

Before using the create_embeddings() function, run the following command to inspect it and review the required arguments:

\df+ azure_openai.*

The Argument data types property in the output of the \df+ azure_openai.* command reveals the list of arguments the function expects.

The first argument is the deployment_name, assigned when your embedding model was deployed in your Azure OpenAI account. To retrieve this value, go to your Azure OpenAI resource in the Azure portal. From there, in the left-hand navigation menu, under Resource Management select the Model deployments item to open Azure OpenAI Studio. In Azure OpenAI Studio, on the Deployments tab, copy the Deployment name value associated with the text-embedding-ada-002 model deployment.

Using this information, run a query to update each record in the bill_summaries table, inserting the generated vector embeddings for the bill_text field into the bill_vector column using the azure_openai.create_embeddings() function. Replace {your-deployment-name} with the Deployment name value you copied from the Azure OpenAI Studio Deployments tab, and then run the following command:

UPDATE bill_summaries b
SET bill_vector = azure_openai.create_embeddings('{your-deployment-name}', b.bill_text);

Execute the following query to view the embedding generated for the first record in the table. You can run \x first if the output is difficult to read.

SELECT bill_vector FROM bill_summaries LIMIT 1;

Each embedding is a vector of floating point numbers, such that the distance between two embeddings in the vector space is correlated with semantic similarity between two inputs in the original format.

Perform a vector similarity search

Vector similarity is a method used to measure how similar two items are by representing them as vectors, which are series of numbers. Vectors are often used to perform searches using LLMs. Vector similarity is commonly calculated using distance metrics, such as Euclidean distance or cosine similarity. Euclidean distance measures the straight-line distance between two vectors in the n-dimensional space, while cosine similarity measures the cosine of the angle between two vectors.

To enable more efficient searching over the vector field by creating an index on bill_summaries using cosine distance and HNSW, which is short for Hierarchical Navigable Small World. HNSW allows pgvector to use the latest graph-based algorithms to approximate nearest-neighbor queries.

CREATE INDEX ON bill_summaries USING hnsw (bill_vector vector_cosine_ops);

With everything now in place, you're now ready to execute a cosine similarity search query against the database.

In the query below, the embeddings are generated for an input question and then cast to a vector array (::vector), which allows it to be compared against the vectors stored in the bill_summaries table.

SELECT bill_id, title FROM bill_summaries
ORDER BY bill_vector <=> azure_openai.create_embeddings('embeddings', 'Show me bills relating to veterans entrepreneurship.')::vector
LIMIT 3;

The query uses the <=> vector operator, which represents the "cosine distance" operator used to calculate the distance between two vectors in a multi-dimensional space.

Integrate Azure Cognitive Services

The Azure AI services integrations included in the azure_cognitive schema of the azure_ai extension provide a rich set of AI Language features accessible directly from the database. The functionalities include sentiment analysis, language detection, key phrase extraction, entity recognition, and text summarization. Access to these capabilities is enabled through the Azure AI Language service.

To review the complete Azure AI capabilities accessible through the extension, view the Integrate Azure Database for PostgreSQL - Flexible Server with Azure Cognitive Services.

Set the Azure AI Language service endpoint and key

As with the azure_openai functions, to successfully make calls against Azure AI services using the azure_ai extension, you must provide the endpoint and a key for your Azure AI Language service. Retrieve those values by navigating to your Language service resource in the Azure portal, from the left/hand menu, under Resource Management, select Keys and Endpoint item. Copy your endpoint and access key. You can use either KEY1 or KEY2.

In the command below, replace the {endpoint} and {api-key} tokens with values you retrieved from the Azure portal, then run the commands from the psql command prompt to add your values to the configuration table.

SELECT azure_ai.set_setting('azure_cognitive.endpoint','{endpoint}');
SELECT azure_ai.set_setting('azure_cognitive.subscription_key', '{api-key}');

Summarize bills

To demonstrate some of the capabilities of the azure_cognitive functions of the azure_ai extension, you generate a summary of each bill. The azure_cognitive schema provides two functions for summarizing text, summarize_abstractive and summarize_extractive. Abstractive summarization produces a summary that captures the main concepts from input text but might not use identical words. Extractive summarization assembles a summary by extracting critical sentences from the input text.

To use the Azure AI Language service's ability to generate new, original content, you use the summarize_abstractive function to create a summary of text input. Use the \df meta-command from psql again, this time to look specifically at the azure_cognitive.summarize_abstractive function.

\df azure_cognitive.summarize_abstractive

The Argument data types property in the output of the \df azure_cognitive.summarize_abstractive command reveals the list of arguments the function expects.

The summarize_abstractive functionfunction requires the following arguments: azure_cognitive.summarize_abstractive(text TEXT, language TEXT).

The following query against the bill_summaries table uses the summarize_abstractive function to generate a new one-sentence summary for the text of a bill, allowing you to incorporate the power of generative AI directly into your queries.

SELECT
    bill_id,
    azure_cognitive.summarize_abstractive(bill_text, 'en', sentence_count => 1) one_sentence_summary
FROM bill_summaries
WHERE bill_id = '112_hr2873';

The function can also be used to write data into your database tables. Modify the bill_summaries table to add a new column for storing the one-sentence summaries in the database.

ALTER TABLE bill_summaries
ADD COLUMN one_sentence_summary TEXT;

Next, update the table with the summaries. The summarize_abstractive function returns an array of text (text[]). The array_to_string function converts the return value to its string representation. In the query below, the throw_on_error argument has been set to false. This setting allows the summarization process to continue if an error occurs.

UPDATE bill_summaries b
SET one_sentence_summary = array_to_string(azure_cognitive.summarize_abstractive(b.bill_text, 'en', throw_on_error => false, sentence_count => 1), ' ', '')
where one_sentence_summary is NULL;

In the output, you might notice a warning about an invalid document for which an appropriate summarization couldn't be generated. This warning results from setting throw_on_error to false in the above query. If that flag were left to the default of true, the query fails, and no summaries would have been written to the database. To view the record that threw the warning, execute the following:

SELECT bill_id, one_sentence_summary FROM bill_summaries WHERE one_sentence_summary is NULL;

You can then query the bill_summaries table to view the new, one-sentence summaries generated by the azure_ai extension for the other records in the table.

SELECT bill_id, one_sentence_summary FROM bill_summaries LIMIT 5;

Conclusion

Congratulations, you just learned how to use the azure_ai extension to integrate large language models and generative AI capabilities into your database.

Related content

• How to use PostgreSQL extensions in Azure Database for PostgreSQL - Flexible Server
• Learn how to generate embeddings with Azure OpenAI
• Azure OpenAI Service embeddings models
• Understand embeddings in Azure OpenAI Service
• What is Azure AI Language?
• What is Azure OpenAI Service?