The differences between "Term", "Match Phrase", and "Query String" queries on ElasticSearch

Elasticsearch provides different types of queries for searching text and structured data. Here’s a breakdown of the differences between "Term", "Match Phrase", and "Query String" queries:

1. Term Query

?? Use case: Exact match for structured data (keywords, IDs, numbers, etc.). ?? Behavior:

• Does not analyze the text (i.e., no tokenization or lowercasing).
• Searches for an exact value in a field.
• Best for keyword fields or numeric fields.

Example: Searching for a specific keyword

{
    "query": {
        "term": {
            "status": "active"
        }
    }
}
        

• Finds documents where the "status" field is exactly "active".
• If status is indexed as a text field, this query won't work properly.

? Best for:

• Filtering by IDs, booleans, enums, categories, or fields that use .keyword.

2. Match Phrase Query

?? Use case: Search for an exact phrase in text (word order matters). ?? Behavior:

• Analyzes the text (tokenization, stemming, etc.).
• Matches documents where all words appear in the same order.

Example: Searching for an exact phrase

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

• Matches "The quick brown fox jumps", but not "The fox is quick and brown."
• Respects word order and proximity.

? Best for:

• Finding exact phrases in full-text search.

3. Query String Query

?? Use case: Allows advanced search syntax (AND, OR, wildcards, fuzzy matching). ?? Behavior:

• Can search multiple fields at once.
• Supports boolean operators (AND, OR).
• Allows wildcards (*, ?) and fuzzy searches (~).

Example: Searching with complex conditions

{
    "query": {
        "query_string": {
            "query": "(quick OR fast) AND (fox OR dog)",
            "default_field": "description"
        }
    }
}
        

• Matches documents containing either "quick" or "fast" AND either "fox" or "dog".
• Supports wildcards: { "query": { "query_string": { "query": "qu?ck bro*n", "default_field": "description" } } } Matches "quick brown" and "quack broken".

? Best for:

• Power users who need complex queries.
• Full-text search with boolean logic.

Comparison Table

When to Use Each?

• Use term for filtering structured data (e.g., user_id, status, tags.keyword).
• Use match_phrase when searching for exact phrases in text fields.
• Use query_string when you need advanced search with boolean logic, wildcards, or fuzzy matching.

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