Query return the search difference on elasticsearch - elasticsearch

How would the following query look:
Scenario:
I have two bases (base 1 and 2), with 1 column each, I would like to see the difference between them, that is, what exists in base 1 that does not exist in base 2, considering the fictitious names of the columns as hostname.
Example:
Selected value of Base1.Hostname is for Base2.Hostname?
YES → DO NOT RETURN
NO → RETURN
I have this in python for the following function:
def diff(first, second):
second = set (second)
return [item for item in first if item not in second]
Example match equal:
GET /base1/_search
{
"query": {
"multi_match": {
"query": "webserver",
"fields": [
"hostname"
],
"type": "phrase"
}
}
}
I would like to migrate this architecture to elastic search in order to generate forecast in the future with the frequency of change of these search in the bases

This could be done with aggregation.
Collect all the hostname from base1 & base2 index
For each hostname count occurrences in base2
Keep only the buckets that have base2 count 0
GET base*/_search
{
"size": 0,
"aggs": {
"all": {
"composite": {
"size": 10,
"sources": [
{
"host": {
"terms": {
"field": "hostname"
}
}
}
]
},
"aggs": {
"base2": {
"filter": {
"match": {
"_index": "base2"
}
}
},
"index_count_bucket_filter": {
"bucket_selector": {
"buckets_path": {
"base2_count": "base2._count"
},
"script": "params.base2_count == 0"
}
}
}
}
}
}
By the way don't forget to use pagination to get rest of the result.
References :
https://www.elastic.co/guide/en/elasticsearch/reference/current/search-aggregations-bucket-composite-aggregation.html
https://discuss.elastic.co/t/data-set-difference-between-fields-on-different-indexes/160015/4

Related

ElasticSearch _knn_search query on multiple fields

I'm using ES 8.2. I'd like to use approximate method of _knn_search on more than 1 vector. Below I've attached my current code searching on a single vector. So far as I've read _knn_search does not support search on nested fields.
Alternatively, I can use multi index search. One index, one vector, one search, sum up all results together. However, I need to store all these vectors together in one index as I need also to perform filtration on some other fields besides vectors for knn search.
Thus, the question is if there is a work around how I can perform _knn_search on more than 1 vector?
search_vector = np.zeros(512).tolist()
es_query = {
"knn": {
"field": "feature_vector_1.vector",
"query_vector": search_vector,
"k": 100,
"num_candidates": 1000
},
"filter": [
{
"range": {
"feature_vector_1.match_prc": {
"gt": 10
}
}
}
],
"_source": {
"excludes": ["feature_vector_1.vector", "feature_vector_2.vector"]
}
}
The last working query that I've end up with is
es_query = {
"knn": {
"field": "feature_vector_1.vector",
"query_vector": search_vector,
"k": 1000,
"num_candidates": 1000
},
"filter": [
{
"function_score": {
"query": {
"match_all": {}
},
"script_score": {
"script": {
"source": """
double value = dotProduct(params.queryVector, 'feature_vector_2.vector');
return 100 * (1 + value) / 2;
""",
"params": {
"queryVector": search_vector
}
},
}
}
}
],
"_source": {
"excludes": ["feature_vector_1.vector", "feature_vector_2.vector"]
}
}
However, it is not true AKNN on 2 vectors but still working option if performance of such query satisfies your expectations.
the below seems to be working for me for combining KNN searches, taking the average of multiple cosine similarity scores. Note that this is a little different than the original request, since it performs a brute force search, but you can still filter the results up front by replacing the match_all bit.
GET my-index/_search
{
"query": {
"script_score": {
"query": {
"match_all": {}
},
"script": {
"source": "(cosineSimilarity(params.vector1, 'my-vector1') + cosineSimilarity(params.vector2, 'my-vector2'))/2 + 1.0",
"params": {
"vector1": [
1.3012068271636963,
...
0.23468133807182312
],
"vector2": [
-0.49404603242874146,
...
-0.15835021436214447
]
}
}
}
}
}

How to write an Elasticsearch query that aggregates by a field, and for each one of another field?

Given an index with documents of the following format
{
"userA": "user1",
"relation": 10,
"userB": "user2"
}
How to create an aggregation query that will display for each user (from a given list), the sum of 'relation's between them.
for example: given userX, userY
result will be:
{
user4: {user1: 100, user2: 300, user3: 350},
...
userX: {user4: 123, user5: 456}
}
I tried to do it using 2 separate queries like that (the second one with userB instead in the aggs field)
GET myindex*/_search
{
"query": {
"bool": {
"must": [
{
"terms": {
"userA": [<input user ids>]
}
},
{
"terms": {
"userB": [<input user ids>]
}
]
}
},
"aggs": {
"connections": {
"terms": {
"field": "userA" //// Second query with `userB`
},
"aggs": {
"privateConversationCount": {
"avg": {
"field": "privateConversationCount"
}
}
}
}
}
}
But this is not correct, it requires a nested aggregation.
How could I write a query that will answer that need?

Elasticsearch partial update based on Aggregation result

I want to update partially all objects that are based on aggregation result.
Here is my object:
{
"name": "name",
"identificationHash": "aslkdakldjka",
"isDupe": false,
...
}
My goal is to set isDupe to "true" for all documents where "identificationHash" is there more than 2 times.
Currently what I'm doing is:
I get all the documents that "isDupe" = false with a Term aggregation on "identificationHash" for a min_doc_count of 2.
{
"query": {
"bool": {
"must": [
{
"term": {
"isDupe": {
"value": false,
"boost": 1
}
}
}
]
}
},
"aggregations": {
"identificationHashCount": {
"terms": {
"field": "identificationHash",
"size": 10000,
"min_doc_count": 2
}
}
}
}
With the aggregation result, I do a bulk update with a script where "ctx._source.isDupe=true" for all identificationHash that match my aggregation result.
I repeat step 1 and 2 until there is no more result from the aggregation query.
My question is: Is there a better solution to that problem? Can I do the same thing with one script query without looping with batch of 1000 identification hash?
There's no solution that I know of that allows you to do this in on shot. However, there's a way to do it in two steps, without having to iterate over several batches of hashes.
The idea is to first identify all the hashes to be updated using a feature called Transforms, which is nothing else than a feature that leverages aggregations and builds a new index out of the aggregation results.
Once that new index has been created by your transform, you can use it as a terms lookup mechanism to run your update by query and update the isDupe boolean for all documents having a matching hash.
So, first, we want to create a transform that will create a new index featuring documents containing all duplicate hashes that need to be updated. This is achieved using a scripted_metric aggregation whose job is to identify all hashes occurring at least twice and for which isDupe: false. We're also aggregating by week, so for each week, there's going to be a document containing all duplicates hashes for that week.
PUT _transform/dup-transform
{
"source": {
"index": "test-index",
"query": {
"term": {
"isDupe": "false"
}
}
},
"dest": {
"index": "test-dups",
"pipeline": "set-id"
},
"pivot": {
"group_by": {
"week": {
"date_histogram": {
"field": "lastModifiedDate",
"calendar_interval": "week"
}
}
},
"aggregations": {
"dups": {
"scripted_metric": {
"init_script": """
state.week = -1;
state.hashes = [:];
""",
"map_script": """
// gather all hashes from each shard and count them
def hash = doc['identificationHash.keyword'].value;
// set week
state.week = doc['lastModifiedDate'].value.get(IsoFields.WEEK_OF_WEEK_BASED_YEAR).toString();
// initialize hashes
if (!state.hashes.containsKey(hash)) {
state.hashes[hash] = 0;
}
// increment hash
state.hashes[hash] += 1;
""",
"combine_script": "return state",
"reduce_script": """
def hashes = [:];
def week = -1;
// group the hash counts from each shard and add them up
for (state in states) {
if (state == null) return null;
week = state.week;
for (hash in state.hashes.keySet()) {
if (!hashes.containsKey(hash)) {
hashes[hash] = 0;
}
hashes[hash] += state.hashes[hash];
}
}
// only return the hashes occurring at least twice
return [
'week': week,
'hashes': hashes.keySet().stream().filter(hash -> hashes[hash] >= 2)
.collect(Collectors.toList())
]
"""
}
}
}
}
}
Before running the transform, we need to create the set-id pipeline (referenced in the dest section of the transform) that will define the ID of the target document that is going to contain the hashes so that we can reference it in the terms query for updating documents:
PUT _ingest/pipeline/set-id
{
"processors": [
{
"set": {
"field": "_id",
"value": "{{dups.week}}"
}
}
]
}
We're now ready to start the transform to generate the list of hashes to update and it's as simple as running this:
POST _transform/dup-transform/_start
When it has run, the destination index test-dups will contain one document that looks like this:
{
"_index" : "test-dups",
"_type" : "_doc",
"_id" : "44",
"_score" : 1.0,
"_source" : {
"week" : "2021-11-01T00:00:00.000Z",
"dups" : {
"week" : "44",
"hashes" : [
"12345"
]
}
}
},
Finally, we can run the update by query as follows (add as many terms queries as weekly documents in the target index):
POST test/_update_by_query
{
"query": {
"bool": {
"minimum_should_match": 1,
"should": [
{
"terms": {
"identificationHash": {
"index": "test-dups",
"id": "44",
"path": "dups.hashes"
}
}
},
{
"terms": {
"identificationHash": {
"index": "test-dups",
"id": "45",
"path": "dups.hashes"
}
}
}
]
}
},
"script": {
"source": "ctx._source.isDupe = true;"
}
}
That's it in two simple steps!! Try it out and let me know.

Boolean AND with exact matches oin Elasticsearch

In our Elasticsearch collection of products, we have an an array of hashes, called "nutrients". A partial example of the data would be:
"_source": {
"quantity": "150.0",
"id": 1001,
"barcode": "7610809001066",
"nutrients": [
{
"per_hundred": "1010.0",
"name_fr": "Énergie",
"per_portion": "758.0",
"name_de": "Energie",
"per_day": "9.0",
"name_it": "Energia",
"name_en": "Energy"
},
{
"per_hundred": "242.0",
"name_fr": "Énergie (kCal)",
"per_portion": "181.0",
"name_de": "Energie (kCal)",
"per_day": "9.0",
"name_it": "Energia (kCal)",
"name_en": "Energy (kCal)"
},
{
"per_hundred": "18.0",
"name_fr": "Matières grasses",
"per_portion": "13.5",
"name_de": "Fett",
"per_day": "19.0",
"name_it": "Grassi",
"name_en": "Fat"
},
In the search, we are trying to bring back the products based on an exact match of two of the fields contained in the nutrients array. What I am finding is the conditions seemed to be OR and not AND.
The two attempts have been:
"query": {
"bool": {
"must": [
{ "match": { "nutrients.name_fr": "Énergie" } },
{ "match": { "nutrients.per_hundred": "242.0" } }
]
}
}
}
and
"query": {
"filtered": {
"filter": {
"and": [
{ "term": { "nutrients.name_fr": "Énergie" } },
{ "term": { "nutrients.per_hundred": "242.0" } }
]
}
}
}
Both of these are in fact bringing back entries with Énergie and 242.0, but are also match on different name_fr, eg:
{
"per_hundred": "242.0",
"name_fr": "Acide folique",
"per_portion": "96.0",
"name_de": "Folsäure",
"per_day": "48.0",
"name_it": "Acido folico",
"name_en": "Folic acid"
},
They are also matching on a non exact match, i.e: matching also on "Énergie (kCal)" when we want to match only on "Énergie"
On your first problem:
You have to make the nutrients field nested, so you can query each object inside it for itself Elasticsearch Nested Objects.

How to check field data is numeric when using inline Script in ElasticSearch

Per our requirement we need to find the max ID of the document before adding new document. Problem here is doc may contain string data also So had to use inline script on the elastic query to find out max id only for the document which has integer data otherwise returning 0. am using following inline script query to find max-key but not working. can you help me onthis ?.
{
"size":0,
"query":
{"bool":
{"filter":[
{"term":
{"Name":
{
"value":"Test2"
}
}}
]
}},
"aggs":{
"MaxId":{
"max":{
"field":"Key","script":{
"inline":"((doc['Key'].value).isNumber()) ? Integer.parseInt(doc['Key'].value) : 0"}}
}
}
}
The error is because the max aggregation only supports numeric fields, i.e. you cannot specify a string field (i.e. Key) in a max aggregation.
Simply remove the "field":"Key" part and only keep the script part
{
"size": 0,
"query": {
"bool": {
"filter": [
{
"term": {
"Name": "Test2"
}
}
]
}
},
"aggs": {
"MaxId": {
"max": {
"script": {
"source": "((doc['Key'].value).isNumber()) ? Integer.parseInt(doc['Key'].value) : 0"
}
}
}
}
}

Resources