Standard analyzer
The standard
analyzer is the default analyzer used when no other analyzer is specified. It is designed to provide a basic and efficient approach to generic text processing.
This analyzer consists of the following tokenizers and token filters:
standard
tokenizer: Removes most punctuation and splits text on spaces and other common delimiters.lowercase
token filter: Converts all tokens to lowercase, ensuring case-insensitive matching.stop
token filter: Removes common stopwords, such as “the”, “is”, and “and”, from the tokenized output.
Example
Use the following command to create an index named my_standard_index
with a standard
analyzer:
PUT /my_standard_index
{
"mappings": {
"properties": {
"my_field": {
"type": "text",
"analyzer": "standard"
}
}
}
}
Parameters
You can configure a standard
analyzer with the following parameters.
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 . |
stopwords | Optional | String or list of strings | A string specifying a predefined list of stopwords (such as _english_ ) or an array specifying a custom list of stopwords. Default is _none_ . |
stopwords_path | Optional | String | The path (absolute or relative to the config directory) to the file containing a list of stop words. |
Configuring a custom analyzer
Use the following command to configure an index with a custom analyzer that is equivalent to the standard
analyzer:
PUT /my_custom_index
{
"settings": {
"analysis": {
"analyzer": {
"my_custom_analyzer": {
"type": "custom",
"tokenizer": "standard",
"filter": [
"lowercase",
"stop"
]
}
}
}
}
}
Generated tokens
Use the following request to examine the tokens generated using the analyzer:
POST /my_custom_index/_analyze
{
"analyzer": "my_custom_analyzer",
"text": "The slow turtle swims away"
}
The response contains the generated tokens:
{
"tokens": [
{"token": "slow","start_offset": 4,"end_offset": 8,"type": "<ALPHANUM>","position": 1},
{"token": "turtle","start_offset": 9,"end_offset": 15,"type": "<ALPHANUM>","position": 2},
{"token": "swims","start_offset": 16,"end_offset": 21,"type": "<ALPHANUM>","position": 3},
{"token": "away","start_offset": 22,"end_offset": 26,"type": "<ALPHANUM>","position": 4}
]
}