Decompounder

The decompounder filter splits compound words into individual components based on a specified dictionary, making it easier to search for parts of compound terms. This filter is particularly useful for languages that frequently use compound words, such as German.

Configuration

The decompounder filter is a custom filter in Milvus. To use it, specify "type": "decompounder" in the filter configuration, along with a word_list parameter that provides the dictionary of word components to recognize.

analyzer_params = {
    "tokenizer": "standard",
    "filter":[{
        "type": "decompounder", # Specifies the filter type as decompounder
        "word_list": ["dampf", "schiff", "fahrt", "brot", "backen", "automat"],
    }],
}

Map<String, Object> analyzerParams = new HashMap<>();
analyzerParams.put("tokenizer", "standard");
analyzerParams.put("filter",
        Collections.singletonList(
                new HashMap<String, Object>() {{
                    put("type", "decompounder");
                    put("word_list", Arrays.asList("dampf", "schiff", "fahrt", "brot", "backen", "automat"));
                }}
        )
);

const analyzer_params = {
    "tokenizer": "standard",
    "filter":[{
        "type": "decompounder", // Specifies the filter type as decompounder
        "word_list": ["dampf", "schiff", "fahrt", "brot", "backen", "automat"],
    }],
};

analyzerParams = map[string]any{"tokenizer": "standard",
    "filter": []any{map[string]any{
        "type":       "decompounder",
        "word_list": []string{"dampf", "schiff", "fahrt", "brot", "backen", "automat"},
    }}}

# restful
analyzerParams='{
  "tokenizer": "standard",
  "filter": [
    {
      "type": "decompounder",
      "word_list": [
        "dampf",
        "schiff",
        "fahrt",
        "brot",
        "backen",
        "automat"
      ]
    }
  ]
}'

The decompounder filter accepts the following configurable parameters.

Parameter	Description
word_list	A list of word components used to split compound terms. This dictionary determines how compound words are decomposed into individual terms.

The decompounder filter operates on the terms generated by the tokenizer, so it must be used in combination with a tokenizer. For a list of tokenizers available in Milvus, refer to Standard Tokenizer and its sibling pages.

After defining analyzer_params, you can apply them to a VARCHAR field when defining a collection schema. This allows Milvus to process the text in that field using the specified analyzer for efficient tokenization and filtering. For details, refer to Example use.

Examples

Before applying the analyzer configuration to your collection schema, verify its behavior using the run_analyzer method.

Analyzer configuration

analyzer_params = {
    "tokenizer": "standard",
    "filter":[{
        "type": "decompounder", # Specifies the filter type as decompounder
        "word_list": ["dampf", "schiff", "fahrt", "brot", "backen", "automat"],
    }],
}

Map<String, Object> analyzerParams = new HashMap<>();
analyzerParams.put("tokenizer", "standard");
analyzerParams.put("filter",
        Collections.singletonList(
                new HashMap<String, Object>() {{
                    put("type", "decompounder");
                    put("word_list", Arrays.asList("dampf", "schiff", "fahrt", "brot", "backen", "automat"));
                }}
        )
);

// javascript

analyzerParams = map[string]any{"tokenizer": "standard",
    "filter": []any{map[string]any{
        "type":       "decompounder",
        "word_list": []string{"dampf", "schiff", "fahrt", "brot", "backen", "automat"},
    }}}

# restful
analyzerParams='{
  "tokenizer": "standard",
  "filter": [
    {
      "type": "decompounder",
      "word_list": [
        "dampf",
        "schiff",
        "fahrt",
        "brot",
        "backen",
        "automat"
      ]
    }
  ]
}'

Verification using run_analyzerCompatible with Milvus 2.5.11+

# Sample text to analyze
sample_text = "dampfschifffahrt brotbackautomat"

# Run the standard analyzer with the defined configuration
result = MilvusClient.run_analyzer(sample_text, analyzer_params)
print(result)

// java

// javascript

// go

# restful

Expected output

['dampf', 'schiff', 'fahrt', 'brotbackautomat']