Pagination (from/size) in Elasticsearch - Mini Project: Build & Apply

Pagination (from/size) in Elasticsearch

📖 Scenario: You are working with an Elasticsearch index that stores information about books in a library. The library has thousands of books, and you want to show the books page by page on a website.

🎯 Goal: Build an Elasticsearch query that uses from and size to paginate through the list of books, showing a specific page of results.

📋 What You'll Learn

Create a query body with a match_all query to get all books

Add a from parameter to skip a certain number of books

Add a size parameter to limit the number of books returned

Print the final query JSON to see the pagination parameters

💡 Why This Matters

🌍 Real World

Pagination is used in websites and apps to show large lists of items in smaller chunks, making it easier for users to browse.

💼 Career

Understanding Elasticsearch pagination helps backend developers and data engineers efficiently retrieve and display search results.

1

Create the base query body

Create a variable called query_body that contains a dictionary with a query key. The value should be a dictionary with match_all as an empty dictionary.

Elasticsearch

# Create the base query_body with a match_all query
# Your code here

Need a hint?

Use query_body = {"query": {"match_all": {}}} to get all documents.

2

Add the from parameter for pagination start

Add a key from with the value 10 to the query_body dictionary to skip the first 10 books.

Elasticsearch

query_body = {
    "query": {
        "match_all": {}
    }
}
# Add the from parameter to skip 10 books
# Your code here

Need a hint?

Add "from": 10 at the top level of query_body.

3

Add the size parameter to limit results

Add a key size with the value 5 to the query_body dictionary to limit the results to 5 books per page.

Elasticsearch

query_body = {
    "query": {
        "match_all": {}
    },
    "from": 10
}
# Add the size parameter to limit results to 5
# Your code here

Need a hint?

Add "size": 5 at the top level of query_body.

4

Print the final query body

Print the query_body variable to display the complete Elasticsearch query with pagination.

Elasticsearch

query_body = {
    "query": {
        "match_all": {}
    },
    "from": 10,
    "size": 5
}
# Print the query_body
# Your code here

Need a hint?

Use print(query_body) to show the query.