Using wildcards in combination with exact match in the r library Elasticsearch - r

Question

Likely due to my inexperience in Elasticsearch (and the R library Elastic), I cannot figure out how to formulate a search query in such a way that an exact match is combined with a wildcard.
docs_create(index="test",type="x", body=list(txt="this is a test"))
count(index='test', type='x',q="'a test'",default_operator="AND")
... returns one match.
count(index='test', type='x',q="'a te*'",default_operator="AND")
... returns no match (although I hoped to get one match too).
count(index='test', type='x',q="'a te/*'",default_operator="AND")
... produces an error (Error: 400 - all shards failed).
count(index='test', type='x',q="'a te'//*",default_operator="AND")
... returns no match.
Any help is welcome! Thank you.
PS. If this is impossible using the count function, using the Search function is fine too to solve my issue (using the body parameter).

Answer 1

#peterk what does the query without the single quotes return?
Can you try it like this:
count(index='test', type='x', q="a te*", default_operator="AND")

Answer 2

One thing to note, try connect(errors = "complete") to get more verbose errors - basically the same info the elastic server gives
count(index='test', type='x',q="'a te/*'",default_operator="AND")
#> Error: 400 - all shards failed
#> ES stack trace:
#>
#> type: query_shard_exception
#> reason: Failed to parse query ['a te/*']
#> index_uuid: xbZ5ANNBRwqxEsqPqS05Dg
#> index: test
Which suggests that that query is not valid
In general it's easier to use elastic::Search() as its more flexible - and set size parameter to 0 so you just get a count of records matched.
It's still not clear to me what is the exact part. Is it a te or a test or something else?

Answer 3

After a great week of sleep, I figured out how to get this done (using the match_phrase_prefix option:
docs_create(index="test",type="x", body=list(txt="this is a test"))
body <-
'{
"query": {
"match_phrase_prefix" : {
"txt" : {
"query" : "a te",
"max_expansions" : 10
}
}
}
}'
Search(index='test',body=body)