Construct a query
Each Solr query is comprised of a number of parameters. These are like arguments to a function in R, but they are entered as parts of a URL.
The most common parameters are:
q
: The query. This is likesubset()
ordplyr::filter()
in R.fl
: What fields are returned for the documents that match your query (q
). If not set, all fields are returned.rows
: The maximum number of documents to return. Solr will truncate your result if the result size is greater thanrows
.sort
: Sorts the result by the values in the given Solr field (e.g., sort by date uploaded).
The query (q
) parameter uses a syntax that looks like field:value
, where field
is one of the Solr fields and value
is an expression. The expression can match a specific value exactly, e.g., q=identifier:arctic-data.7747.1
or q=identifier:"doi:10.5065/D60P0X4S"
, which finds the Solr document for a specific Object by PID
(identifier).
In the second example, the DOI PID
is surrounded in
double quotes. This is because Solr has
reserved
characters, of which :
is one, so we have to help Solr
by surrounding values with reserved characters in them in quotes or by
escaping them.
To view the list of query-able parameters on the Arctic Data Center and their descriptions, you can visit https://arcticdata.io/metacat/d1/mn/v2/query/solr.