OpenSearch/docs/reference/analysis/tokenizers/standard-tokenizer.asciidoc
James Rodewig 5a2c6f0d4f
[DOCS] http -> https, remove outdated plugin docs (#60380) (#60545)
Plugin discovery documentation contained information about installing
Elasticsearch 2.0 and installing an oracle JDK, both of which is no
longer valid.

While noticing that the instructions used cleartext HTTP to install
packages, this commit replaces HTTPs links instead of HTTP where possible.

In addition a few community links have been removed, as they do not seem
to exist anymore.

Co-authored-by: Alexander Reelsen <alexander@reelsen.net>
2020-07-31 16:16:31 -04:00

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[[analysis-standard-tokenizer]]
=== Standard tokenizer
++++
<titleabbrev>Standard</titleabbrev>
++++
The `standard` tokenizer provides grammar based tokenization (based on the
Unicode Text Segmentation algorithm, as specified in
https://unicode.org/reports/tr29/[Unicode Standard Annex #29]) and works well
for most languages.
[discrete]
=== Example output
[source,console]
---------------------------
POST _analyze
{
"tokenizer": "standard",
"text": "The 2 QUICK Brown-Foxes jumped over the lazy dog's bone."
}
---------------------------
/////////////////////
[source,console-result]
----------------------------
{
"tokens": [
{
"token": "The",
"start_offset": 0,
"end_offset": 3,
"type": "<ALPHANUM>",
"position": 0
},
{
"token": "2",
"start_offset": 4,
"end_offset": 5,
"type": "<NUM>",
"position": 1
},
{
"token": "QUICK",
"start_offset": 6,
"end_offset": 11,
"type": "<ALPHANUM>",
"position": 2
},
{
"token": "Brown",
"start_offset": 12,
"end_offset": 17,
"type": "<ALPHANUM>",
"position": 3
},
{
"token": "Foxes",
"start_offset": 18,
"end_offset": 23,
"type": "<ALPHANUM>",
"position": 4
},
{
"token": "jumped",
"start_offset": 24,
"end_offset": 30,
"type": "<ALPHANUM>",
"position": 5
},
{
"token": "over",
"start_offset": 31,
"end_offset": 35,
"type": "<ALPHANUM>",
"position": 6
},
{
"token": "the",
"start_offset": 36,
"end_offset": 39,
"type": "<ALPHANUM>",
"position": 7
},
{
"token": "lazy",
"start_offset": 40,
"end_offset": 44,
"type": "<ALPHANUM>",
"position": 8
},
{
"token": "dog's",
"start_offset": 45,
"end_offset": 50,
"type": "<ALPHANUM>",
"position": 9
},
{
"token": "bone",
"start_offset": 51,
"end_offset": 55,
"type": "<ALPHANUM>",
"position": 10
}
]
}
----------------------------
/////////////////////
The above sentence would produce the following terms:
[source,text]
---------------------------
[ The, 2, QUICK, Brown, Foxes, jumped, over, the, lazy, dog's, bone ]
---------------------------
[discrete]
=== Configuration
The `standard` tokenizer accepts the following parameters:
[horizontal]
`max_token_length`::
The maximum token length. If a token is seen that exceeds this length then
it is split at `max_token_length` intervals. Defaults to `255`.
[discrete]
=== Example configuration
In this example, we configure the `standard` tokenizer to have a
`max_token_length` of 5 (for demonstration purposes):
[source,console]
----------------------------
PUT my-index-000001
{
"settings": {
"analysis": {
"analyzer": {
"my_analyzer": {
"tokenizer": "my_tokenizer"
}
},
"tokenizer": {
"my_tokenizer": {
"type": "standard",
"max_token_length": 5
}
}
}
}
}
POST my-index-000001/_analyze
{
"analyzer": "my_analyzer",
"text": "The 2 QUICK Brown-Foxes jumped over the lazy dog's bone."
}
----------------------------
/////////////////////
[source,console-result]
----------------------------
{
"tokens": [
{
"token": "The",
"start_offset": 0,
"end_offset": 3,
"type": "<ALPHANUM>",
"position": 0
},
{
"token": "2",
"start_offset": 4,
"end_offset": 5,
"type": "<NUM>",
"position": 1
},
{
"token": "QUICK",
"start_offset": 6,
"end_offset": 11,
"type": "<ALPHANUM>",
"position": 2
},
{
"token": "Brown",
"start_offset": 12,
"end_offset": 17,
"type": "<ALPHANUM>",
"position": 3
},
{
"token": "Foxes",
"start_offset": 18,
"end_offset": 23,
"type": "<ALPHANUM>",
"position": 4
},
{
"token": "jumpe",
"start_offset": 24,
"end_offset": 29,
"type": "<ALPHANUM>",
"position": 5
},
{
"token": "d",
"start_offset": 29,
"end_offset": 30,
"type": "<ALPHANUM>",
"position": 6
},
{
"token": "over",
"start_offset": 31,
"end_offset": 35,
"type": "<ALPHANUM>",
"position": 7
},
{
"token": "the",
"start_offset": 36,
"end_offset": 39,
"type": "<ALPHANUM>",
"position": 8
},
{
"token": "lazy",
"start_offset": 40,
"end_offset": 44,
"type": "<ALPHANUM>",
"position": 9
},
{
"token": "dog's",
"start_offset": 45,
"end_offset": 50,
"type": "<ALPHANUM>",
"position": 10
},
{
"token": "bone",
"start_offset": 51,
"end_offset": 55,
"type": "<ALPHANUM>",
"position": 11
}
]
}
----------------------------
/////////////////////
The above example produces the following terms:
[source,text]
---------------------------
[ The, 2, QUICK, Brown, Foxes, jumpe, d, over, the, lazy, dog's, bone ]
---------------------------