Date histogram in Elasticsearch - Mini Project: Build & Apply

Date histogram

📖 Scenario: You work for a company that collects sales data with timestamps. You want to see how many sales happened each day.

🎯 Goal: Create an Elasticsearch query that groups sales by day using a date histogram aggregation.

📋 What You'll Learn

Create an Elasticsearch query with a date histogram aggregation named sales_per_day.

Use the field sale_date for the date histogram.

Set the interval to day.

Include a match_all query to get all documents.

💡 Why This Matters

🌍 Real World

Date histograms help businesses analyze trends over time, like daily sales or website visits.

💼 Career

Knowing how to write date histogram queries is useful for data analysts and backend developers working with time-series data in Elasticsearch.

1

Create the base query

Create a variable called query and set it to a JSON object with a query key containing a match_all query.

Elasticsearch

query = {
    "query": {
        "match_all": {}
    }
}
# Your code here

Need a hint?

The match_all query returns all documents.

2

Add the date histogram aggregation

Add an aggs key to the query variable. Inside aggs, create a date histogram aggregation named sales_per_day that uses the field sale_date and sets the interval to day.

Elasticsearch

query = {
    "query": {
        "match_all": {}
    },
    # Add aggs here
}
# Your code here

Need a hint?

The date_histogram aggregation groups documents by date intervals.

3

Complete the query structure

Ensure the query variable is a complete JSON object with query and aggs keys as described. No changes needed if already done.

Elasticsearch

query = {
    "query": {
        "match_all": {}
    },
    "aggs": {
        "sales_per_day": {
            "date_histogram": {
                "field": "sale_date",
                "calendar_interval": "day"
            }
        }
    }
}
# Your code here

Need a hint?

Check that the query has both query and aggs keys.

4

Print the final query

Write print(query) to display the complete Elasticsearch query.

Elasticsearch

query = {
    "query": {
        "match_all": {}
    },
    "aggs": {
        "sales_per_day": {
            "date_histogram": {
                "field": "sale_date",
                "calendar_interval": "day"
            }
        }
    }
}

# Print the query
# Your code here

Need a hint?

Use print(query) to see the full query JSON.