elasticsearch comparison between fields - elasticsearch

Let's say I have documents with the following fields:
{field1, field2, ... fieldn}
I need to run some queries where some of the conditions will require a comparison between two or more fields. like fieldX = fieldY
In standard SQL, an example could be:
SELECT * FROM Table1 WHERE farePrice>100 AND originRegion = destinationRegion
I'be been reading some documentation, and it looks "scripting" could be the only way to achieve this? Or are there any other options?

You can use the script filter -
{
"filtered": {
"query": {
"range": {
"farePrice": {
"gt": 100
}
}
},
"filter": {
"script": {
"script": "doc['originRegion'].value == doc['destinationRegion'].value"
}
}
}
}
You can find more information at here and here .

Related

multi fields search query for elasticsearch golang

I have a situation where I need to do elastic search based on multi-field. For Example: I have multiple fields in my postindex and I want to apply condition on four these fields (i.e. userid, channelid, createat, teamid) to meet my search requirement. When value of all these fields matched then search query displays results and if one of these is not match with values in postindex then it display no result.
I am trying to make a multifield search query for go-elasticsearch to search data from my post index. For the searcquery result four field must match otherwise it display 0 hit/no-result.
So, I think you need to write a following query :
GET postindex/_search
{
"query": {
"bool": {
"minimum_should_match": 1,
"should": [
{
"bool": {
"must": [
{
"term": {
"userid": {
"value": "mcqmycxpyjrddkie9mr13txaqe"
}
}
},
{
"term": {
"channelid": {
"value": "dnoihmrinins3qrm6bb9175ume"
}
}
},
{
"range": {
"createat": {
"gt": 1672909114890
}
}
}
]
}
},
{
"term": {
"teamid": {
"value": "qomrg11o8b8ijxoy8hrcnweoay"
}
}
}
]
}
}
}
In here, there is a bool query with should in parent scope, which is like OR. And inside the should there is another bool query with must which is like AND. We can also write the query shorter, but this will be better for you to understand.

Is it possible to access a query term in a script field?

I would like to construct an elasticsearch query in which I can search for a term and on-the-fly compute a new field for each found document, which is calculated based on some existing fields as well as the query term. Is this possible?
For example, let's say in my EL query I am searching for documents which have the keyword "amsterdam" in the "text" field.
"filter": [
{
"match_phrase": {
"text": {
"query": "amsterdam"
}
}
}]
Now I would also like to have a script field in my query, which computes some value based on other fields as well as the query.
So far, I have only found how to access the other fields of a document though, using doc['someOtherField'], for example
"script_fields" : {
"new_field" : {
"script" : {
"lang": "painless",
"source": "if (doc['citizens'].value > 10000) {
return "large";
}
return "small";"
}
}
}
How can I integrate the query term, e.g. if I wanted to add to the if statement "if the query term starts with a-e"?
You're on the right track but script_fields are primarily used to post-process your documents' attributes — they won't help you filter any docs because they're run after the query phase.
With that being said, you can use scripts to filter your documents through script queries. Before you do that, though, you should explore alternatives.
In other words, scripts should be used when all other mechanisms and techniques have been exhausted.
Back to your example. I see three possibilities off the top of my head.
Match phrase prefix queries as a group of bool-should subqueries:
POST your-index/_search
{
"query": {
"bool": {
"must": [
{
"bool": {
"should": [
{
"match_phrase_prefix": {
"text_field": "a"
}
},
{
"match_phrase_prefix": {
"text_field": "b"
}
},
{
"match_phrase_prefix": {
"text_field": "c"
}
},
... till the letter "e"
]
}
}
]
}
}
}
A regexp query:
POST your-index/_search
{
"query": {
"bool": {
"must": [
{
"regexp": {
"text_field": "[a-e].+"
}
}
]
}
}
}
Script queries using .charAt comparisons:
POST your-index/_search
{
"query": {
"bool": {
"must": [
{
"script": {
"script": {
"source": """
char c = doc['text_field.keyword'].value.charAt(0);
return c >= params.gte.charAt(0) && c <= params.lte.charAt(0);
""",
"params": {
"gte": "a",
"lte": "e"
}
}
}
}
]
}
}
}
If you're relatively new to ES and would love to see real-world examples, check out my recently released Elasticsearch Handbook. One chapter is dedicated to scripting and as it turns out, you can achieve a lot with scripts (if of course executed properly).

Elasticsearch : filter results based on the date range

I'm using Elasticsearch 6.6, trying to extract multiple results/records based on multiple values (email_address) passed to the query (Bool) on a date range. For ex: I want to extract information about few employees based on their email_address (annie#test.com, charles#test.com, heman#test.com) and from the period i.e project_date (2019-01-01).
I did use should expression but unfortunately it's pulling all the records from elasticsearch based on the date range i.e. it's even pulling other employees information from project_date 2019-01-01.
{
"query": {
"bool": {
"should": [
{ "match": { "email_address": "annie#test.com" }},
{ "match": { "email_address": "chalavadi#test.com" }}
],
"filter": [
{ "range": { "project_date": { "gte": "2019-08-01" }}}
]
}
}
}
I also tried must expression but getting no result. Could you please help me on finding employees using their email_address with the date range?
Thanks in advance.
Should(Or) clauses are optional
Quoting from this article.
"In a query, if must and filter queries are present, the should query occurrence then helps to influence the score. However, if bool query is in a filter context or has neither must nor filter queries, then at least one of the should queries must match a document."
So in your query should is only influencing the score and not actually filtering the document. You must wrap should in must, or move it in filter(if scoring not required).
GET employeeindex/_search
{
"query": {
"bool": {
"filter": {
"range": {
"projectdate": {
"gte": "2019-01-01"
}
}
},
"must": [
{
"bool": {
"should": [
{
"term": {
"email.raw": "abc#text.com"
}
},
{
"term": {
"email.raw": "efg#text.com"
}
}
]
}
}
]
}
}
}
You can also replace should clause with terms clause as in #AlwaysSunny's answer.
You can do it with terms and range along with your existing query inside filter in more shorter way. Your existing query doesn't work as expected because of should clause, it makes your filter weaker. Read more here:
https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-bool-query.html
{
"query": {
"bool": {
"filter": [
{
"terms": {
"email_address.keyword": [
"annie#test.com", "chalavedi#test.com"
]
}
},
{
"range": {
"project_date": {
"gte": "2019-08-01"
}
}
}
]
}
}
}

how to query fieldA=fieldB in ElasticSearch?

I want to query similary follow's SQL :
select * from talbe where id=cityid
Who know how to implement in es ?
thanks for your answer !
You can do this with a script filter like this:
POST /table/_search
{
"query": {
"bool": {
"filter": {
"script": {
"script": "doc.id.value == doc.cityid.value"
}
}
}
}
}

elastic search where clause with constant rank?How to do this?

I'm new to elastic search. How to generate elastic search equivalent query for
select * from response where pnrno='sampleid'
I know we have to use 'filter' option in elastic search.but we do not need any ranking. (ranking can be constant) so how can I generate query for achieve this
you are correct , you can use filtered query with query clause empty and filters.Filtering a set of documents is to filter the sets upon which query acts to furthur filter/match and calculate relevance.Filters are like bool either match or reject(1/0).
{
"query": {
"filtered": {
"filter": {
"bool": {
"must": [{
"term": {
"FIELD": "VALUE"
}
}]
}
}
}
}
}
The usual way of achieving this is by using the constant_score query with an embedded term filter, like this:
{
"query": {
"constant_score": {
"filter": {
"term": {
"pnrno": "sampleid"
}
}
}
}
}

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