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--- | ||
layout: default | ||
title: Standard | ||
parent: Tokenizers | ||
nav_order: 130 | ||
--- | ||
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# Standard tokenizer | ||
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The `standard` tokenizer is the default tokenizer in OpenSearch. It tokenizes text based on word boundaries using a grammar-based approach that recognizes letters, digits, and other characters like punctuation. It is highly versatile and suitable for many languages because it uses Unicode text segmentation rules ([UAX#29](https://unicode.org/reports/tr29/)) to break text into tokens. | ||
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## Example usage | ||
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The following example request creates a new index named `my_index` and configures an analyzer with a `standard` tokenizer: | ||
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```json | ||
PUT /my_index | ||
{ | ||
"settings": { | ||
"analysis": { | ||
"analyzer": { | ||
"my_standard_analyzer": { | ||
"type": "standard" | ||
} | ||
} | ||
} | ||
}, | ||
"mappings": { | ||
"properties": { | ||
"content": { | ||
"type": "text", | ||
"analyzer": "my_standard_analyzer" | ||
} | ||
} | ||
} | ||
} | ||
``` | ||
{% include copy-curl.html %} | ||
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## Generated tokens | ||
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Use the following request to examine the tokens generated using the analyzer: | ||
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```json | ||
POST /my_index/_analyze | ||
{ | ||
"analyzer": "my_standard_analyzer", | ||
"text": "OpenSearch is powerful, fast, and scalable." | ||
} | ||
``` | ||
{% include copy-curl.html %} | ||
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The response contains the generated tokens: | ||
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```json | ||
{ | ||
"tokens": [ | ||
{ | ||
"token": "opensearch", | ||
"start_offset": 0, | ||
"end_offset": 10, | ||
"type": "<ALPHANUM>", | ||
"position": 0 | ||
}, | ||
{ | ||
"token": "is", | ||
"start_offset": 11, | ||
"end_offset": 13, | ||
"type": "<ALPHANUM>", | ||
"position": 1 | ||
}, | ||
{ | ||
"token": "powerful", | ||
"start_offset": 14, | ||
"end_offset": 22, | ||
"type": "<ALPHANUM>", | ||
"position": 2 | ||
}, | ||
{ | ||
"token": "fast", | ||
"start_offset": 24, | ||
"end_offset": 28, | ||
"type": "<ALPHANUM>", | ||
"position": 3 | ||
}, | ||
{ | ||
"token": "and", | ||
"start_offset": 30, | ||
"end_offset": 33, | ||
"type": "<ALPHANUM>", | ||
"position": 4 | ||
}, | ||
{ | ||
"token": "scalable", | ||
"start_offset": 34, | ||
"end_offset": 42, | ||
"type": "<ALPHANUM>", | ||
"position": 5 | ||
} | ||
] | ||
} | ||
``` | ||
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## Parameters | ||
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The `standard` tokenizer can be configured with the following parameter. | ||
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Parameter | Required/Optional | Data type | Description | ||
:--- | :--- | :--- | :--- | ||
`max_token_length` | Optional | Integer | Sets the maximum length of the produced token. If this length is exceeded, the token is split into multiple tokens at the length configured in `max_token_length`. Default is `255`. | ||
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