Overview
There are three different match types in ElasticSearch
- term - the whole field must match. This has a limit of matching only the first 256 characters.
- wildcard - ability to search for partial words. Example: break* will match break and breaking. This also has a limit of 256 characters.
- match_phrase - This matches on a word boundary and can go longer than 256 characters.
Case insensitive searches are super slow. Create a lowercase field in ElasticSearch instead.
Example queries that can be used for ElasticSearch and Lucene
# Count items in an index
GET customer_index/_count
{
"query" : {
"match_all" : {}
}
}
# Get top 200 from the customer_index
GET customer_index/_search
{
"size" : 200,
"query" : {
"match_all" : {}
}
}
# Return the top 200 products that are movies
GET product_index/_search
{
"size" : 200,
"query" : {
"bool" : {
"must" : [
{
"match" : {
"category" : "Movie"
}
}
]
}
}
}
# Search for any products that have DVD in the name with a wildcard
GET product_index/_search
{
"size" : 200,
"query" : {
"wildcard" : {
"name" : {
"value" : "*DVD*"
}
}
}
}
# Get an aggregate list of product categories sorted alphabetically
GET product_index/_search
{
"size" : 0,
"aggs" : {
"category" : {
"terms" : {
"field" : "category.keyword",
"order" : {
"_key" : "asc"
}
}
}
}
}
# Get a list of physical products that do not have a category
GET product_index/_search
{
"size" : 200,
"query" : {
"bool" : {
"must_not" : [
{
"exists" : {
"field" : "category"
}
}
],
"minimum_should_match" : 1,
"should" : [
{
"match" : {
"product_type" : {
"query" : "Physical"
}
}
}
]
}
}
}
# Group by Aggregate
GET _search/
{
"size" : 0,
"query" : {
"bool" : {
"must" : [
{
"match" : {
"product_type" : "Physical"
}
},
{
"wildcard" : {
"category.keyword" : {
"value" : "*DVD*"
}
}
}
]
}
},
"aggs" : {
"group_by_column" : {
"terms" : {
"field" : "category.keyword",
"size" : 10000
}
}
}
}
# Perform a search and order by using functions
GET product_index/_search
{
"size": 200,
"query": {
"function_score": {
"query": {
"bool": {
"must": [
{
"bool": {
"minimum_should_match": 1,
"should": [
{
"term": {
"category.keyword": "Books"
}
},
{
"term": {
"category.keyword": "Movies"
}
}
]
}
}
],
"minimum_should_match": 1,
"should": [
{
"match_phrase": {
"nameLowercase": "journey"
}
},
{
"match_phrase": {
"descriptionLowercase": "journey"
}
}
]
}
},
"functions": [
{
"filter": {
"bool": {
"must": [
{
"term": {
"nameLowercase.keyword": "journey"
}
}
]
}
},
"weight": 3
},
{
"filter": {
"bool": {
"must": [
{
"match_phrase": {
"nameLowercase": "journey"
}
}
]
}
},
"weight": 2
},
{
"filter": {
"bool": {
"must": [
{
"match_phrase": {
"descriptionLowercase": "journey"
}
}
]
}
},
"weight": 1
}
],
"score_mode": "first",
"boost_mode": "replace"
}
},
"sort": {
"_score": {
"order": "desc"
}
}
}
