Dis max query in Elasticsearch - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a dis_max query with two match queries.

Elasticsearch

{
  "query": {
    "dis_max": {
      "queries": [
        { "match": { "title": "[1]" } },
        { "match": { "description": "search text" } }
      ]
    }
  }
}

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

Asearch query

Bquery text

Ctext search

Dsearch text

Attempts:

3 left

💡 Hint

Common Mistakes

Using a different phrase than 'search text' in the match query.

Putting the phrase outside the quotes.

The dis_max query combines multiple queries and uses the highest score. Here, the first match query should search for "search text" in the title field.

2fill in blank

medium

Complete the code to set the tie_breaker parameter to 0.7 in the dis_max query.

Elasticsearch

{
  "query": {
    "dis_max": {
      "tie_breaker": [1],
      "queries": [
        { "match": { "title": "search text" } },
        { "match": { "description": "search text" } }
      ]
    }
  }
}

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

A0

B0.7

C0.3

D1.0

Attempts:

3 left

💡 Hint

Common Mistakes

Using an integer instead of a decimal.

Setting tie_breaker to 0 or 1 which changes behavior drastically.

The tie_breaker parameter controls how much the scores of non-best matching queries contribute. Setting it to 0.7 means 70% of the other scores add to the max score.

3fill in blank

hard

Fix the error in the dis_max query by completing the missing field name.

Elasticsearch

{
  "query": {
    "dis_max": {
      "queries": [
        { "match": { "[1]": "search text" } },
        { "match": { "description": "search text" } }
      ]
    }
  }
}

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

Atitle

Bcontent

Csummary

Dbody

Attempts:

3 left

💡 Hint

Common Mistakes

Using a field name that does not exist in the index.

Leaving the field name blank or misspelled.

The first match query must specify the field name to search. "title" is the correct field name here.

4fill in blank

hard

Fill both blanks to create a dis_max query with a tie_breaker and two match queries on 'title' and 'content'.

Elasticsearch

{
  "query": {
    "dis_max": {
      "tie_breaker": [1],
      "queries": [
        { "match": { "title": "search text" } },
        { "match": { "[2]": "search text" } }
      ]
    }
  }
}

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

A0.5

B0.9

Ccontent

Ddescription

Attempts:

3 left

💡 Hint

Common Mistakes

Using an invalid tie_breaker value.

Using the wrong field name for the second match query.

The tie_breaker is set to 0.5 to balance scores. The second match query searches the 'content' field.

5fill in blank

hard

Fill all three blanks to build a dis_max query with tie_breaker, boost, and two match queries on 'title' and 'summary'.

Elasticsearch

{
  "query": {
    "dis_max": {
      "tie_breaker": [1],
      "boost": [2],
      "queries": [
        { "match": { "title": "search text" } },
        { "match": { "[3]": "search text" } }
      ]
    }
  }
}

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

A0.3

B1.5

Csummary

Ddescription

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up boost and tie_breaker values.

Using incorrect field names in match queries.

The tie_breaker is 0.3 to allow some contribution from other queries. The boost is 1.5 to increase overall score weight. The second match query searches the 'summary' field.

Practice

1. What is the main purpose of the dis_max query in Elasticsearch?

easy

A. To select the highest score from multiple queries to find the best match

B. To combine all scores from multiple queries by summing them

C. To filter documents based on a single exact match

D. To sort documents alphabetically by a field

Solution

1. Step 1: Understand the dis_max query behavior

   The dis_max query evaluates multiple queries and picks the highest score among them for each document.

2. Step 2: Compare with other scoring methods

   Unlike sum or filter queries, dis_max focuses on the best single match score, not combined or filtered results.

3. Final Answer:

   To select the highest score from multiple queries to find the best match -> Option A

4. Quick Check:

   dis_max picks highest score = A [OK]

Hint: Remember: dis_max picks the best single score, not sums [OK]

Common Mistakes:

• Thinking dis_max sums scores from all queries
• Confusing dis_max with filter queries
• Assuming dis_max sorts documents alphabetically

2. Which of the following is the correct syntax to use a dis_max query with two match queries in Elasticsearch?

easy

A. {\"dis_max\": {\"queries\": {\"match\": {\"field1\": \"value1\"}, \"match\": {\"field2\": \"value2\"}}}}

B. {\"dis_max\": [{\"match\": {\"field1\": \"value1\"}}, {\"match\": {\"field2\": \"value2\"}}]}

C. {\"dis_max\": {\"queries\": [{\"match\": {\"field1\": \"value1\"}}, {\"match\": {\"field2\": \"value2\"}}]}}

D. {\"dis_max\": {\"query\": [{\"match\": {\"field1\": \"value1\"}}, {\"match\": {\"field2\": \"value2\"}}]}}

Solution

1. Step 1: Check the dis_max query structure

   The dis_max query requires a queries array containing individual query objects.

2. Step 2: Validate the JSON syntax

   {\"dis_max\": {\"queries\": [{\"match\": {\"field1\": \"value1\"}}, {\"match\": {\"field2\": \"value2\"}}]}} correctly uses queries as an array with two match queries inside separate objects.

3. Final Answer:

   {"dis_max": {"queries": [{"match": {"field1": "value1"}}, {"match": {"field2": "value2"}}]}} -> Option C

4. Quick Check:

   dis_max uses queries array = D [OK]

Hint: dis_max needs a 'queries' array, not 'query' or object [OK]

Common Mistakes:

• Using 'query' instead of 'queries' key
• Passing queries as an object instead of an array
• Omitting the array brackets around queries

3. Given this Elasticsearch query snippet using dis_max with tie_breaker set to 0.3:

{
  "dis_max": {
    "queries": [
      { "match": { "title": "apple" } },
      { "match": { "description": "apple" } }
    ],
    "tie_breaker": 0.3
  }
}

What effect does the tie_breaker parameter have on the scoring?

medium

A. It adds 30% of the scores from non-highest matching queries to the final score

B. It multiplies the highest score by 0.3

C. It ignores all but the highest scoring query

D. It subtracts 0.3 from the highest score

Solution

1. Step 1: Understand tie_breaker in dis_max

   The tie_breaker adds a fraction of the scores from other matching queries to the highest score.

2. Step 2: Apply the 0.3 value meaning

   With tie_breaker 0.3, 30% of the other query scores are added to the highest score, boosting documents matching multiple queries.

3. Final Answer:

   It adds 30% of the scores from non-highest matching queries to the final score -> Option A

4. Quick Check:

   tie_breaker 0.3 adds 30% other scores = C [OK]

Hint: tie_breaker adds fraction of other scores to highest score [OK]

Common Mistakes:

• Thinking tie_breaker multiplies highest score directly
• Assuming tie_breaker ignores other queries
• Believing tie_breaker subtracts from scores

4. You wrote this dis_max query but it returns an error:

{
  "dis_max": {
    "queries": {
      { "match": { "field1": "value1" } },
      { "match": { "field2": "value2" } }
    }
  }
}

What is the error and how to fix it?

medium

A. The dis_max query requires a boost parameter

B. The queries value should be an array, not an object; replace curly braces with square brackets

C. The match queries must be inside a 'query' key, not 'queries'

D. The field names must be strings without quotes

Solution

1. Step 1: Identify the queries structure error

   The queries key must hold an array of query objects, but curly braces {} were used, making it an object.

2. Step 2: Correct the syntax

   Replace the curly braces around the queries with square brackets [] to form a valid array.

3. Final Answer:

   The queries value should be an array, not an object; replace curly braces with square brackets -> Option B

4. Quick Check:

   queries must be array [] not object {} = A [OK]

Hint: Use [] for queries array, not {} [OK]

Common Mistakes:

• Using curly braces instead of square brackets for queries
• Adding unnecessary boost parameter causing errors
• Removing quotes from field names

5. You want to boost the importance of a dis_max query compared to other queries in your Elasticsearch search. Which is the correct way to apply a boost to the entire dis_max query?

hard

A. { "dis_max": { "boost": 2.0, "tie_breaker": 0.5 } }

B. { "dis_max": { "queries": [...], "boost": "high" } }

C. { "dis_max": { "queries": [...], "tie_breaker": 2.0 } }

D. { "dis_max": { "queries": [...], "boost": 2.0 } }

Solution

1. Step 1: Understand boost usage in dis_max

   The boost parameter is applied at the dis_max query level to increase its overall importance.

2. Step 2: Validate correct boost syntax

   Boost must be a numeric value; { "dis_max": { "queries": [...], "boost": 2.0 } } correctly places boost: 2.0 inside dis_max alongside queries.

3. Final Answer:

   { "dis_max": { "queries": [...], "boost": 2.0 } } -> Option D

4. Quick Check:

   Boost is numeric and inside dis_max = B [OK]

Hint: Put numeric boost inside dis_max alongside queries [OK]

Common Mistakes:

• Using non-numeric boost values like strings
• Placing boost outside dis_max query
• Confusing tie_breaker with boost