Match phrase query in Elasticsearch - Mini Project: Build & Apply

Match Phrase Query in Elasticsearch

📖 Scenario: You are working with a small collection of book data stored in Elasticsearch. You want to find books that contain an exact phrase in their description.

🎯 Goal: Build an Elasticsearch query that uses a match_phrase to find books with the exact phrase "deep learning" in their description.

📋 What You'll Learn

Create an index called books with sample book documents

Add a configuration variable for the phrase to search

Write a match_phrase query using the phrase variable

Print the query JSON to see the final search request

💡 Why This Matters

🌍 Real World

Searching for exact phrases in text fields is common in search engines, like finding books or articles containing specific terms.

💼 Career

Understanding how to build match_phrase queries is useful for roles involving search engine development, data retrieval, and Elasticsearch administration.

1

Create the books index with sample data

Create a variable called books_index that holds a JSON object with two book documents. Each document should have id, title, and description. Use these exact entries: {"id": 1, "title": "AI Basics", "description": "An introduction to artificial intelligence."} and {"id": 2, "title": "Deep Learning Guide", "description": "A comprehensive guide to deep learning techniques."}

Elasticsearch

# Create a variable called books_index with two book documents
# Your code here

Hint

Use a list of dictionaries to represent the books. Each dictionary should have keys: id, title, and description.

2

Set the phrase to search

Create a variable called search_phrase and set it to the string "deep learning".

Elasticsearch

books_index = [
    {"id": 1, "title": "AI Basics", "description": "An introduction to artificial intelligence."},
    {"id": 2, "title": "Deep Learning Guide", "description": "A comprehensive guide to deep learning techniques."}
]
# Create a variable called search_phrase with the value "deep learning"
# Your code here

Hint

Assign the exact string "deep learning" to the variable search_phrase.

3

Build the match_phrase query

Create a variable called query that holds a JSON object for an Elasticsearch match_phrase query. The query should search the description field for the phrase stored in search_phrase.

Elasticsearch

books_index = [
    {"id": 1, "title": "AI Basics", "description": "An introduction to artificial intelligence."},
    {"id": 2, "title": "Deep Learning Guide", "description": "A comprehensive guide to deep learning techniques."}
]
search_phrase = "deep learning"
# Create a variable called query with a match_phrase query on description using search_phrase
# Your code here

Hint

Use the match_phrase key inside query with the field description set to search_phrase.

4

Print the final query JSON

Write a print statement to display the query variable.

Elasticsearch

books_index = [
    {"id": 1, "title": "AI Basics", "description": "An introduction to artificial intelligence."},
    {"id": 2, "title": "Deep Learning Guide", "description": "A comprehensive guide to deep learning techniques."}
]
search_phrase = "deep learning"
query = {
    "query": {
        "match_phrase": {
            "description": search_phrase
        }
    }
}
# Print the query variable
# Your code here

Hint

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

Practice

1. What does a match_phrase query in Elasticsearch do?

easy

A. Searches only for single words, ignoring phrases.

B. Searches for any of the words in the query, regardless of order.

C. Searches for an exact sequence of words in the given order.

D. Searches for documents with numeric values only.

Solution

1. Step 1: Understand the purpose of match_phrase

   The match_phrase query looks for the exact sequence of words in the order they appear in the query.

2. Step 2: Compare with other query types

   Unlike match query, which finds any word in any order, match_phrase requires the phrase to appear exactly.

3. Final Answer:

   Searches for an exact sequence of words in the given order. -> Option C

4. Quick Check:

   match_phrase = exact word order search [OK]

Hint: Remember: match_phrase means exact words in exact order [OK]

Common Mistakes:

• Confusing match_phrase with match query
• Thinking it ignores word order
• Assuming it works only for single words

2. Which of the following is the correct syntax for a match_phrase query in Elasticsearch?

easy

A. { "match": { "field": "search text" } }

B. { "match_phrase": { "field": "search text" } }

C. { "term": { "field": "search text" } }

D. { "range": { "field": { "gte": 10 } } }

Solution

1. Step 1: Identify the correct query type

   The match_phrase query uses the key "match_phrase" with the field and the phrase to search.

2. Step 2: Check the syntax format

   The correct syntax is a JSON object with "match_phrase" as the key and the field name mapping to the phrase string.

3. Final Answer:

   { "match_phrase": { "field": "search text" } } -> Option B

4. Quick Check:

   Correct JSON syntax for match_phrase = { "match_phrase": { "field": "search text" } } [OK]

Hint: Look for "match_phrase" key with field and phrase inside braces [OK]

Common Mistakes:

• Using "match" instead of "match_phrase"
• Confusing with "term" or "range" queries
• Incorrect JSON structure or missing braces

3. Given this Elasticsearch query:

{ "query": { "match_phrase": { "description": "quick brown fox" } } }

Which documents will match?

medium

A. Documents containing the words "fox brown quick" in any order.

B. Documents containing any of the words "quick", "brown", or "fox" in any order.

C. Documents containing the phrase "quick fox brown" exactly.

D. Documents containing the phrase "quick brown fox" exactly in that order.

Solution

1. Step 1: Analyze the match_phrase query

   The query searches for the exact phrase "quick brown fox" in the field "description".

2. Step 2: Understand phrase matching behavior

   Only documents with the words in the exact order "quick brown fox" will match, not any other order or partial words.

3. Final Answer:

   Documents containing the phrase "quick brown fox" exactly in that order. -> Option D

4. Quick Check:

   Exact phrase match = Documents containing the phrase "quick brown fox" exactly in that order. [OK]

Hint: match_phrase requires exact word order in the phrase [OK]

Common Mistakes:

• Assuming word order does not matter
• Thinking partial word matches count
• Confusing with match query behavior

4. You wrote this query but it returns no results:

{ "query": { "match_phrase": { "title": "fast runner" } } }

Your documents contain the phrase "runner fast". What is the issue?

medium

A. The phrase order is incorrect; match_phrase requires exact order.

B. The field name "title" is invalid.

C. match_phrase does not support multi-word phrases.

D. The query syntax is wrong; it should use "match" instead.

Solution

1. Step 1: Check phrase order in query vs documents

   The query searches for "fast runner" but documents have "runner fast" which is reversed.

2. Step 2: Understand match_phrase behavior

   match_phrase requires the exact word order, so reversed order causes no matches.

3. Final Answer:

   The phrase order is incorrect; match_phrase requires exact order. -> Option A

4. Quick Check:

   Exact order matters in match_phrase = The phrase order is incorrect; match_phrase requires exact order. [OK]

Hint: Check word order carefully when match_phrase returns no hits [OK]

Common Mistakes:

• Ignoring word order importance
• Assuming match_phrase works like match
• Changing field name unnecessarily

5. You want to find documents containing the phrase "data science" but also allow a gap of one word between "data" and "science". Which match_phrase query option should you use?

hard

A. { "match_phrase": { "field": "data science", "slop": 1 } }

B. { "match_phrase": { "field": "data science", "boost": 1 } }

C. { "match": { "field": "data science", "slop": 1 } }

D. { "term": { "field": "data science" } }

Solution

1. Step 1: Understand phrase slop in match_phrase

   The "slop" parameter allows words to appear with gaps or reordered within a limit.

2. Step 2: Identify correct syntax for slop

   Using "slop": 1 inside the match_phrase query allows one word gap between "data" and "science".

3. Final Answer:

   { "match_phrase": { "field": "data science", "slop": 1 } } -> Option A

4. Quick Check:

   Use slop to allow gaps in match_phrase = { "match_phrase": { "field": "data science", "slop": 1 } } [OK]

Hint: Add "slop" to match_phrase to allow word gaps [OK]

Common Mistakes:

• Using slop with match instead of match_phrase
• Confusing boost with slop
• Using term query for phrase matching