Solr search

Description

Returns only matched documents, and doesn't return other items, including facets, groups, mlt, stats, and highlights.

Usage

solr_search(conn, name = NULL, params = list(q = "*:*"), body = NULL,
  callopts = list(), raw = FALSE, parsetype = "df", concat = ",",
  optimizeMaxRows = TRUE, minOptimizedRows = 50000L, ...)

Arguments

Value

XML, JSON, a list, or data.frame

Parameters

• q Query terms, defaults to '*:*', or everything.

• sort Field to sort on. You can specify ascending (e.g., score desc) or descending (e.g., score asc), sort by two fields (e.g., score desc, price asc), or sort by a function (e.g., sum(x_f, y_f) desc, which sorts by the sum of x_f and y_f in a descending order).

• start Record to start at, default to beginning.

• rows Number of records to return. Default: 10.

• pageDoc If you expect to be paging deeply into the results (say beyond page 10, assuming rows=10) and you are sorting by score, you may wish to add the pageDoc and pageScore parameters to your request. These two parameters tell Solr (and Lucene) what the last result (Lucene internal docid and score) of the previous page was, so that when scoring the query for the next set of pages, it can ignore any results that occur higher than that item. To get the Lucene internal doc id, you will need to add [docid] to the &fl list. e.g., q=*:*&start=10&pageDoc=5&pageScore=1.345&fl=[docid],score

• pageScore See pageDoc notes.

• fq Filter query, this does not affect the search, only what gets returned. This parameter can accept multiple items in a lis or vector. You can't pass more than one parameter of the same name, so we get around it by passing multiple queries and we parse internally

• fl Fields to return, can be a character vector like c('id', 'title'), or a single character vector with one or more comma separated names, like 'id,title'

• defType Specify the query parser to use with this request.

• timeAllowed The time allowed for a search to finish. This value only applies to the search and not to requests in general. Time is in milliseconds. Values <= 0 mean no time restriction. Partial results may be returned (if there are any).

• qt Which query handler used. Options: dismax, others?

• NOW Set a fixed time for evaluating Date based expresions

• TZ Time zone, you can override the default.

• echoHandler If TRUE, Solr places the name of the handle used in the response to the client for debugging purposes. Default:

• echoParams The echoParams parameter tells Solr what kinds of Request parameters should be included in the response for debugging purposes, legal values include:

  • none - don't include any request parameters for debugging

  • explicit - include the parameters explicitly specified by the client in the request

  • all - include all parameters involved in this request, either specified explicitly by the client, or implicit because of the request handler configuration.

• wt (character) One of json, xml, or csv. Data type returned, defaults to 'csv'. If json, uses [jsonlite::fromJSON()] to parse. If xml, uses [xml2::read_xml()] to parse. If csv, uses [read.table()] to parse. 'wt=csv' gives the fastest performance at least in all the cases we have tested in, thus it's the default value for 'wt'

Note

SOLR v1.2 was first version to support csv. See https://issues.apache.org/jira/browse/SOLR-66

References

See http://wiki.apache.org/solr/#Search_and_Indexing for more information.

See Also

solr_highlight(), solr_facet()

Examples

## Not run: 
# Connect to a local Solr instance
(cli <- SolrClient$new())
cli$search("gettingstarted", params = list(q = "features:notes"))

solr_search(cli, "gettingstarted")
solr_search(cli, "gettingstarted", params = list(q = "features:notes"))
solr_search(cli, "gettingstarted", body = list(query = "features:notes"))

(cli <- SolrClient$new(host = "api.plos.org", path = "search", port = NULL))
cli$search(params = list(q = "*:*"))
cli$search(params = list(q = "title:golgi", fl = c('id', 'title')))

cli$search(params = list(q = "*:*", facet = "true"))


# search
solr_search(cli, params = list(q='*:*', rows=2, fl='id'))

# search and return all rows
solr_search(cli, params = list(q='*:*', rows=-1, fl='id'))

# Search for word ecology in title and cell in the body
solr_search(cli, params = list(q='title:"ecology" AND body:"cell"',
  fl='title', rows=5))

# Search for word "cell" and not "body" in the title field
solr_search(cli, params = list(q='title:"cell" -title:"lines"', fl='title',
  rows=5))

# Wildcards
## Search for word that starts with "cell" in the title field
solr_search(cli, params = list(q='title:"cell*"', fl='title', rows=5))

# Proximity searching
## Search for words "sports" and "alcohol" within four words of each other
solr_search(cli, params = list(q='everything:"sports alcohol"~7',
  fl='abstract', rows=3))

# Range searches
## Search for articles with Twitter count between 5 and 10
solr_search(cli, params = list(q='*:*', fl=c('alm_twitterCount','id'),
  fq='alm_twitterCount:[5 TO 50]', rows=10))

# Boosts
## Assign higher boost to title matches than to body matches
## (compare the two calls)
solr_search(cli, params = list(q='title:"cell" abstract:"science"',
  fl='title', rows=3))
solr_search(cli, params = list(q='title:"cell"^1.5 AND abstract:"science"',
  fl='title', rows=3))

# FunctionQuery queries
## This kind of query allows you to use the actual values of fields to
## calculate relevancy scores for returned documents

## Here, we search on the product of counter_total_all and alm_twitterCount
## metrics for articles in PLOS Journals
solr_search(cli, params = list(q="{!func}product($v1,$v2)",
  v1 = 'sqrt(counter_total_all)',
  v2 = 'log(alm_twitterCount)', rows=5, fl=c('id','title'),
  fq='doc_type:full'))

## here, search on the product of counter_total_all and alm_twitterCount,
## using a new temporary field "_val_"
solr_search(cli,
  params = list(q='_val_:"product(counter_total_all,alm_twitterCount)"',
  rows=5, fl=c('id','title'), fq='doc_type:full'))

## papers with most citations
solr_search(cli, params = list(q='_val_:"max(counter_total_all)"',
   rows=5, fl=c('id','counter_total_all'), fq='doc_type:full'))

## papers with most tweets
solr_search(cli, params = list(q='_val_:"max(alm_twitterCount)"',
   rows=5, fl=c('id','alm_twitterCount'), fq='doc_type:full'))

## many fq values
solr_search(cli, params = list(q="*:*", fl=c('id','alm_twitterCount'),
   fq=list('doc_type:full','subject:"Social networks"',
           'alm_twitterCount:[100 TO 10000]'),
   sort='counter_total_month desc'))

## using wt = csv
solr_search(cli, params = list(q='*:*', rows=50, fl=c('id','score'),
  fq='doc_type:full', wt="csv"))
solr_search(cli, params = list(q='*:*', rows=50, fl=c('id','score'),
  fq='doc_type:full'))

# using a proxy
# cli <- SolrClient$new(host = "api.plos.org", path = "search", port = NULL,
#   proxy = list(url = "http://186.249.1.146:80"))
# solr_search(cli, q='*:*', rows=2, fl='id', callopts=list(verbose=TRUE))

# Pass on curl options to modify request
## verbose
solr_search(cli, params = list(q='*:*', rows=2, fl='id'),
  callopts = list(verbose=TRUE))

## End(Not run)