Match query in Elasticsearch - Mini Project: Build & Apply

Elasticsearch Match Query

📖 Scenario: You are working with a collection of books stored in Elasticsearch. Each book has a title and an author. You want to find books by searching for words in their titles.

🎯 Goal: Build an Elasticsearch match query to find books whose titles contain a specific word.

📋 What You'll Learn

Create an index called books with sample book documents

Set a search word in a variable called search_word

Write a match query to find books with titles matching search_word

Print the search query JSON

💡 Why This Matters

🌍 Real World

Searching text fields in Elasticsearch is common for websites and apps that show books, articles, or products.

💼 Career

Knowing how to write match queries helps you build search features and work with Elasticsearch in many developer and data roles.

1

Create the books index with sample data

Create a variable called books that holds a list of dictionaries. Each dictionary should represent a book with keys title and author. Use these exact entries: {"title": "The Great Gatsby", "author": "F. Scott Fitzgerald"}, {"title": "Great Expectations", "author": "Charles Dickens"}, and {"title": "The Grapes of Wrath", "author": "John Steinbeck"}.

Elasticsearch

# Create a list called books with the given book dictionaries
# Your code here

Hint

Use a list with three dictionaries exactly as shown.

2

Set the search word

Create a variable called search_word and set it to the string "Great".

Elasticsearch

books = [
    {"title": "The Great Gatsby", "author": "F. Scott Fitzgerald"},
    {"title": "Great Expectations", "author": "Charles Dickens"},
    {"title": "The Grapes of Wrath", "author": "John Steinbeck"}
]
# Set search_word to "Great"
# Your code here

Hint

Assign the string "Great" to the variable search_word.

3

Write the match query

Create a variable called match_query that holds a dictionary representing an Elasticsearch match query. The query should search the title field for the value in search_word. Use this exact structure: {"query": {"match": {"title": search_word}}}.

Elasticsearch

books = [
    {"title": "The Great Gatsby", "author": "F. Scott Fitzgerald"},
    {"title": "Great Expectations", "author": "Charles Dickens"},
    {"title": "The Grapes of Wrath", "author": "John Steinbeck"}
]
search_word = "Great"
# Create match_query dictionary for match query on title with search_word
# Your code here

Hint

Use a nested dictionary with keys "query", "match", and "title".

4

Print the match query

Write a print statement to display the match_query variable.

Elasticsearch

books = [
    {"title": "The Great Gatsby", "author": "F. Scott Fitzgerald"},
    {"title": "Great Expectations", "author": "Charles Dickens"},
    {"title": "The Grapes of Wrath", "author": "John Steinbeck"}
]
search_word = "Great"
match_query = {"query": {"match": {"title": search_word}}}
# Print the match_query dictionary
# Your code here

Hint

Use print(match_query) to show the query.

Practice

1. What does the match query in Elasticsearch primarily do?

easy

A. Updates documents with new values

B. Finds documents with text similar to the search words

C. Deletes documents matching the query

D. Creates a new index for the documents

Solution

1. Step 1: Understand the purpose of match query

   The match query is designed to find documents that contain text similar to the search words provided.

2. Step 2: Differentiate from other operations

   Deleting, updating, or creating indexes are not functions of the match query; it only searches text.

3. Final Answer:

   Finds documents with text similar to the search words -> Option B

4. Quick Check:

   Match query = text search [OK]

Hint: Match query searches text similarity, not modify data [OK]

Common Mistakes:

• Confusing match query with delete or update operations
• Thinking match query creates indexes
• Assuming match query returns exact matches only

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

easy

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

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

C. { "match": { "field" = "search text" } }

D. { "match": [ "field", "search text" ] }

Solution

1. Step 1: Review correct JSON structure for match query

   The match query requires a JSON object with the field name as key and the search text as value inside another object.

2. Step 2: Identify syntax errors in options

   { "match": { "field": "search text" } } uses correct JSON with colon separators and nested object. Options A, B, and C have syntax errors like missing braces, wrong assignment, or array usage.

3. Final Answer:

   { "match": { "field": "search text" } } -> Option A

4. Quick Check:

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

Hint: Match query uses nested JSON with field: text inside match [OK]

Common Mistakes:

• Using equal sign instead of colon
• Missing curly braces around field and text
• Using array instead of object for field and text

3. Given this Elasticsearch query:

{ "query": { "match": { "title": { "query": "quick brown fox", "operator": "and" } } } }

What does the operator": "and" do in this match query?

medium

A. Returns documents containing all the words 'quick', 'brown', and 'fox'

B. Returns documents containing any of the words 'quick', 'brown', or 'fox'

C. Returns documents containing the exact phrase 'quick brown fox'

D. Returns documents containing none of the words

Solution

1. Step 1: Understand the operator option in match query

   The operator 'and' means all words in the query must be present in the document for a match.

2. Step 2: Compare with other operators

   Operator 'or' would return documents with any word, but 'and' requires all words.

3. Final Answer:

   Returns documents containing all the words 'quick', 'brown', and 'fox' -> Option A

4. Quick Check:

   Operator 'and' = all words required [OK]

Hint: Operator 'and' means all words must appear [OK]

Common Mistakes:

• Confusing 'and' with 'or' operator
• Thinking 'and' means exact phrase match
• Ignoring operator option defaults

4. Identify the error in this match query:

{ "query": { "match": { "content": { "query": "data science", "operator": "AND" } } } }

medium

A. The field name 'content' is invalid

B. The query string must be an array, not a string

C. The operator value should be lowercase 'and', not uppercase 'AND'

D. The match query cannot have an operator option

Solution

1. Step 1: Check operator value case sensitivity

   Elasticsearch expects the operator value to be lowercase 'and' or 'or'. Uppercase 'AND' is invalid.

2. Step 2: Validate other parts of the query

   The field name 'content' is valid, query string can be a string, and match query supports operator option.

3. Final Answer:

   The operator value should be lowercase 'and', not uppercase 'AND' -> Option C

4. Quick Check:

   Operator values are lowercase [OK]

Hint: Operator values must be lowercase 'and' or 'or' [OK]

Common Mistakes:

• Using uppercase 'AND' or 'OR' for operator
• Assuming query must be an array
• Thinking operator option is not allowed

5. You want to find documents where the description field contains either the word 'fast' or 'quick', but not necessarily both. Which match query is correct?

hard

A. { "match": { "description": { "query": "fast quick", "operator": "not" } } }

B. { "match": { "description": { "query": "fast quick", "operator": "and" } } }

C. { "match": { "description": "fast OR quick" } }

D. { "match": { "description": { "query": "fast quick", "operator": "or" } } }

Solution

1. Step 1: Understand the operator 'or' in match query

   Operator 'or' returns documents containing any of the words, so either 'fast' or 'quick' or both.

2. Step 2: Evaluate other options

   B requires both words, C searches for documents containing 'fast', 'OR', and 'quick' (treating OR as literal text), D uses invalid operator 'not'.

3. Final Answer:

   { "match": { "description": { "query": "fast quick", "operator": "or" } } } -> Option D

4. Quick Check:

   Use operator 'or' for any word match [OK]

Hint: Use operator 'or' to match any word in query [OK]

Common Mistakes:

• Using 'and' when 'or' is needed
• Using 'OR' in the search text instead of operator
• Using invalid operator like 'not'