Function score query in Elasticsearch - Mini Project: Build & Apply

Function score query

📖 Scenario: You are working with a search engine that ranks products based on their relevance and popularity. You want to boost the scores of products that have a high number of reviews to show them higher in search results.

🎯 Goal: Create an Elasticsearch function_score query that boosts product scores based on the review_count field using a field value factor.

📋 What You'll Learn

Create a basic match_all query inside the function_score query.

Add a field_value_factor function that uses the review_count field.

Set the factor to 1.2 to boost scores.

Print the complete JSON query.

💡 Why This Matters

🌍 Real World

Boosting product scores based on popularity helps users find the most reviewed and trusted products quickly.

💼 Career

Understanding function score queries is important for roles involving search engine optimization and Elasticsearch query tuning.

1

Create the base query

Create a variable called query and assign it a JSON object with a match_all query inside a function_score query. The structure should be: {"query": {"function_score": {"query": {"match_all": {}}}}}.

Elasticsearch

# Create the base function_score query with match_all
# Your code here

Need a hint?

Start by creating a dictionary named query with the keys exactly as shown.

2

Add the field_value_factor function

Add a functions list inside the function_score query in query. Inside this list, add a dictionary with a field_value_factor key that uses the field review_count.

Elasticsearch

query = {
    "query": {
        "function_score": {
            "query": {
                "match_all": {}
            },
            # Add functions list with field_value_factor here
        }
    }
}
# Your code here

Need a hint?

Inside function_score, add a functions key with a list containing a dictionary for field_value_factor.

3

Set the boost factor

Inside the field_value_factor dictionary, add a factor key with the value 1.2 to boost the score based on review_count.

Elasticsearch

query = {
    "query": {
        "function_score": {
            "query": {
                "match_all": {}
            },
            "functions": [
                {
                    "field_value_factor": {
                        "field": "review_count",
                        # Add factor 1.2 here
                    }
                }
            ]
        }
    }
}
# Your code here

Need a hint?

Add the factor key with value 1.2 inside field_value_factor.

4

Print the final query

Print the variable query to display the complete function score query JSON.

Elasticsearch

query = {
    "query": {
        "function_score": {
            "query": {
                "match_all": {}
            },
            "functions": [
                {
                    "field_value_factor": {
                        "field": "review_count",
                        "factor": 1.2
                    }
                }
            ]
        }
    }
}

# Print the query
# Your code here

Need a hint?

Use print(query) to show the final JSON object.