Greek analyzer
The built-in greek analyzer can be applied to a text field using the following command:
PUT /greek-index
{
"mappings": {
"properties": {
"content": {
"type": "text",
"analyzer": "greek"
}
}
}
}
Stem exclusion
You can use stem_exclusion with this language analyzer using the following command:
PUT index_with_stem_exclusion_greek_analyzer
{
"settings": {
"analysis": {
"analyzer": {
"stem_exclusion_greek_analyzer": {
"type": "greek",
"stem_exclusion": ["αρχή", "έγκριση"]
}
}
}
}
}
Greek analyzer internals
The greek analyzer is built using the following components:
-
Tokenizer:
standard -
Token filters:
- lowercase
- stop (Greek)
- keyword
- stemmer (Greek)
Custom Greek analyzer
You can create a custom Greek analyzer using the following command:
PUT /greek-index
{
"settings": {
"analysis": {
"filter": {
"greek_stop": {
"type": "stop",
"stopwords": "_greek_"
},
"greek_stemmer": {
"type": "stemmer",
"language": "greek"
},
"greek_keywords": {
"type": "keyword_marker",
"keywords": []
}
},
"analyzer": {
"greek_analyzer": {
"type": "custom",
"tokenizer": "standard",
"filter": [
"lowercase",
"greek_stop",
"greek_keywords",
"greek_stemmer"
]
}
}
}
},
"mappings": {
"properties": {
"content": {
"type": "text",
"analyzer": "greek_analyzer"
}
}
}
}
Generated tokens
Use the following request to examine the tokens generated using the analyzer:
POST /greek-index/_analyze
{
"field": "content",
"text": "Οι φοιτητές σπουδάζουν στα ελληνικά πανεπιστήμια. Οι αριθμοί τους είναι 123456."
}
The response contains the generated tokens:
{
"tokens": [
{"token": "φοιτητές","start_offset": 3,"end_offset": 11,"type": "<ALPHANUM>","position": 1},
{"token": "σπουδάζ","start_offset": 12,"end_offset": 22,"type": "<ALPHANUM>","position": 2},
{"token": "στα","start_offset": 23,"end_offset": 26,"type": "<ALPHANUM>","position": 3},
{"token": "ελληνικά","start_offset": 27,"end_offset": 35,"type": "<ALPHANUM>","position": 4},
{"token": "πανεπιστήμ","start_offset": 36,"end_offset": 48,"type": "<ALPHANUM>","position": 5},
{"token": "αριθμοί","start_offset": 53,"end_offset": 60,"type": "<ALPHANUM>","position": 7},
{"token": "τους","start_offset": 61,"end_offset": 65,"type": "<ALPHANUM>","position": 8},
{"token": "είνα","start_offset": 66,"end_offset": 71,"type": "<ALPHANUM>","position": 9},
{"token": "123456","start_offset": 72,"end_offset": 78,"type": "<NUM>","position": 10}
]
}