Why search is Elasticsearch's core purpose - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to perform a basic search query in Elasticsearch.

Elasticsearch

GET /my_index/_search
{
  "query": {
    "match": {
      "message": "[1]"
    }
  }
}

Drag options to blanks, or click blank then click option'

Aquery

Bsearch

Cindex

DElasticsearch

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'search' instead of the actual search term.

Using 'query' or 'index' which are not the search terms.

The match query searches for the term Elasticsearch in the message field.

2fill in blank

medium

Complete the code to filter search results by a specific field value.

Elasticsearch

GET /my_index/_search
{
  "query": {
    "bool": {
      "filter": {
        "term": { "status": "[1]" }
      }
    }
  }
}

Drag options to blanks, or click blank then click option'

Aquery

Bsearch

Cactive

Dindex

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'search' or 'query' which are not valid status values.

Using 'index' which is unrelated to filtering.

The term filter restricts results to documents where status is active.

3fill in blank

hard

Fix the error in the search query to correctly match documents containing the word 'fast'.

Elasticsearch

GET /my_index/_search
{
  "query": {
    "match": {
      "description": "[1]"
    }
  }
}

Drag options to blanks, or click blank then click option'

Afast

Bfastly

Cfaster

Dfastest

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'fastly' which is not a correct word.

Using comparative forms like 'faster' or 'fastest' which change the meaning.

The match query should use the exact word fast to find matching documents.

4fill in blank

hard

Fill both blanks to create a search query that matches documents where the 'title' contains 'Elasticsearch' and the 'published' field is true.

Elasticsearch

GET /my_index/_search
{
  "query": {
    "bool": {
      "must": {
        "match": { "title": "[1]" }
      },
      "filter": {
        "term": { "published": [2] }
      }
    }
  }
}

Drag options to blanks, or click blank then click option'

AElasticsearch

Bfalse

Ctrue

Dsearch

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'false' for the published filter which excludes published documents.

Using 'search' instead of the actual search term.

The match query searches for 'Elasticsearch' in the title, and the term filter ensures only published documents (true) are returned.

5fill in blank

hard

Fill all three blanks to create a search query that returns documents where the 'content' field contains 'fast', the 'views' field is greater than 100, and results are sorted by 'date' descending.

Elasticsearch

GET /my_index/_search
{
  "query": {
    "bool": {
      "must": {
        "match": { "content": "[1]" }
      },
      "filter": {
        "range": { "views": { "[2]": [3] } }
      }
    }
  },
  "sort": [ { "date": "desc" } ]
}

Drag options to blanks, or click blank then click option'

Afast

Bgt

C100

Dgte

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'gte' instead of 'gt' changes the filter condition.

Using values other than 100 for the views filter.

Not sorting results by date descending.

The match query looks for 'fast' in content, the range filter uses 'gt' (greater than) 100 for views, and results are sorted by date descending.

Practice

1. Why is search considered the core purpose of Elasticsearch?

easy

A. Because it is designed to quickly find relevant information in large datasets

B. Because it stores data in relational tables

C. Because it only supports simple keyword matching

D. Because it is mainly used for data visualization

Solution

1. Step 1: Understand Elasticsearch's design goal

   Elasticsearch is built to handle large volumes of data and provide fast search results.

2. Step 2: Identify the main use case

   Its main use is to find relevant information quickly using powerful search queries.

3. Final Answer:

   Because it is designed to quickly find relevant information in large datasets -> Option A

4. Quick Check:

   Core purpose = fast, relevant search [OK]

Hint: Remember Elasticsearch = fast search engine [OK]

Common Mistakes:

• Confusing Elasticsearch with relational databases
• Thinking it only supports simple keyword matching
• Assuming it's mainly for visualization

2. Which Elasticsearch query syntax correctly performs a basic search for the term "apple" in the title field?

easy

A. { "query": { "find": { "title": "apple" } } }

B. { "search": { "term": { "title": "apple" } } }

C. { "query": { "match": { "title": "apple" } } }

D. { "match": { "title": "apple" } }

Solution

1. Step 1: Identify correct query structure

   Elasticsearch uses a query object with a match clause for basic text search.

2. Step 2: Check syntax correctness

   { "query": { "match": { "title": "apple" } } } correctly wraps match inside query and specifies the field and term.

3. Final Answer:

   { "query": { "match": { "title": "apple" } } } -> Option C

4. Quick Check:

   Basic search = query + match [OK]

Hint: Use {"query":{"match":{field:"term"}}} for basic search [OK]

Common Mistakes:

• Using incorrect keys like 'search' or 'find'
• Omitting the 'query' wrapper
• Placing 'match' at the root level

3. Given this Elasticsearch query, what will be the main result returned?

{ "query": { "match": { "description": "fast car" } } }

medium

A. Documents containing the exact phrase 'fast car' only

B. Documents containing either 'fast' or 'car' ranked by relevance

C. Documents containing both words 'fast' and 'car' in any order, but not ranked

D. Documents containing only the word 'fast'

Solution

1. Step 1: Understand the match query behavior

   The match query analyzes the text and searches for documents containing any of the words.

2. Step 2: Analyze how results are ranked

   Results are scored and ranked by relevance based on term frequency and other factors.

3. Final Answer:

   Documents containing either 'fast' or 'car' ranked by relevance -> Option B

4. Quick Check:

   Match query = OR search + relevance ranking [OK]

Hint: Match query finds any word and ranks results [OK]

Common Mistakes:

• Assuming match requires exact phrase
• Thinking match returns only documents with all words
• Ignoring relevance ranking

4. Identify the error in this Elasticsearch query that aims to search for "blue sky" in the title field:

{ "query": { "match": { "title": ["blue", "sky"] } } }

medium

A. The field name 'title' is invalid

B. The 'match' query cannot be used inside 'query'

C. The query is missing a 'filter' clause

D. The value for 'title' should be a string, not an array

Solution

1. Step 1: Check the value type for 'match' query

   The match query expects a string value, not an array.

2. Step 2: Confirm correct query structure

   Using an array causes a syntax error; the correct form is a single string with the phrase.

3. Final Answer:

   The value for 'title' should be a string, not an array -> Option D

4. Quick Check:

   Match value = string, not array [OK]

Hint: Match query values must be strings, not lists [OK]

Common Mistakes:

• Passing arrays instead of strings to match
• Misplacing match outside query
• Assuming filter is mandatory

5. You want to build a search feature that returns documents containing the word "coffee" but excludes those that mention "tea". Which Elasticsearch query correctly achieves this?

hard

A. { "query": { "bool": { "must": { "match": { "content": "coffee" } }, "must_not": { "match": { "content": "tea" } } } } }

B. { "query": { "match": { "content": "coffee AND NOT tea" } } }

C. { "query": { "term": { "content": "coffee" } }, "filter": { "term": { "content": "tea" } } }

D. { "query": { "bool": { "should": { "match": { "content": "coffee" } }, "filter": { "match": { "content": "tea" } } } } }

Solution

1. Step 1: Use a boolean query to combine conditions

   The bool query allows combining must and must_not clauses for inclusion and exclusion.

2. Step 2: Specify 'must' for 'coffee' and 'must_not' for 'tea'

   This ensures documents contain 'coffee' but exclude those mentioning 'tea'.

3. Final Answer:

   { "query": { "bool": { "must": { "match": { "content": "coffee" } }, "must_not": { "match": { "content": "tea" } } } } } -> Option A

4. Quick Check:

   Bool query with must and must_not = correct filter [OK]

Hint: Use bool query with must and must_not for include/exclude [OK]

Common Mistakes:

• Using AND NOT inside match query string
• Misusing filter clause for exclusion
• Using should instead of must for required terms