The Standard Query Parser

Sample Responses

This section presents examples of responses from the standard query parser.

The URL below submits a simple query and requests the XML Response Writer to use indentation to make the XML response more readable.

http://localhost:8983/solr/techproducts/select?q=id:SP2514N&wt=xml

Results:

<response>
<responseHeader><status>0</status><QTime>1</QTime></responseHeader>
<result numFound="1" start="0">
 <doc>
  <arr name="cat"><str>electronics</str><str>hard drive</str></arr>
  <arr name="features"><str>7200RPM, 8MB cache, IDE Ultra ATA-133</str>
    <str>NoiseGuard, SilentSeek technology, Fluid Dynamic Bearing (FDB) motor</str></arr>
  <str name="id">SP2514N</str>
  <bool name="inStock">true</bool>
  <str name="manu">Samsung Electronics Co. Ltd.</str>
  <str name="name">Samsung SpinPoint P120 SP2514N - hard drive - 250 GB - ATA-133</str>
  <int name="popularity">6</int>
  <float name="price">92.0</float>
  <str name="sku">SP2514N</str>
 </doc>
</result>
</response>

Here’s an example of a query with a limited field list.

http://localhost:8983/solr/techproducts/select?q=id:SP2514N&fl=id+name&wt=xml

Results:

<response>
<responseHeader><status>0</status><QTime>2</QTime></responseHeader>
<result numFound="1" start="0">
 <doc>
  <str name="id">SP2514N</str>
  <str name="name">Samsung SpinPoint P120 SP2514N - hard drive - 250 GB - ATA-133</str>
 </doc>
</result>
</response>

Term Modifiers

Solr supports a variety of term modifiers that add flexibility or precision, as needed, to searches. These modifiers include wildcard characters, characters for making a search "fuzzy" or more general, and so on. The sections below describe these modifiers in detail.

Wildcard Searches

Solr’s standard query parser supports single and multiple character wildcard searches within single terms. Wildcard characters can be applied to single terms, but not to search phrases.

Fuzzy Searches

Solr’s standard query parser supports fuzzy searches based on the Damerau-Levenshtein Distance or Edit Distance algorithm. Fuzzy searches discover terms that are similar to a specified term without necessarily being an exact match. To perform a fuzzy search, use the tilde ~ symbol at the end of a single-word term. For example, to search for a term similar in spelling to "roam," use the fuzzy search:

roam~

This search will match terms like roams, foam, & foams. It will also match the word "roam" itself.

An optional distance parameter specifies the maximum number of edits allowed, between 0 and 2, defaulting to 2. For example:

roam~1

This will match terms like roams & foam - but not foams since it has an edit distance of "2".

Proximity Searches

A proximity search looks for terms that are within a specific distance from one another.

To perform a proximity search, add the tilde character ~ and a numeric value to the end of a search phrase. For example, to search for a "apache" and "jakarta" within 10 words of each other in a document, use the search:

"jakarta apache"~10

The distance referred to here is the number of term movements needed to match the specified phrase. In the example above, if "apache" and "jakarta" were 10 spaces apart in a field, but "apache" appeared before "jakarta", more than 10 term movements would be required to move the terms together and position "apache" to the right of "jakarta" with a space in between.

Existence Searches

An existence search for a field matches all documents where a value exists for that field. To query for a field existing, simply use a wildcard instead of a term in the search.

field:*

A field will be considered to "exist" if it has any value, even values which are often considered "not existent". (e.g., NaN, "", etc.)

Range Searches

A range search specifies a range of values for a field (a range with an upper bound and a lower bound). The query matches documents whose values for the specified field or fields fall within the range. Range queries can be inclusive or exclusive of the upper and lower bounds. Sorting is done lexicographically, except on numeric fields. For example, the range query below matches all documents whose popularity field has a value between 52 and 10,000, inclusive.

popularity:[52 TO 10000]

Range queries are not limited to date fields or even numerical fields. You could also use range queries with non-date fields:

title:{Aida TO Carmen}

This will find all documents whose titles are between Aida and Carmen, but not including Aida and Carmen.

The brackets around a query determine its inclusiveness.

Wildcards, *, can also be used for either or both endpoints to specify an open-ended range query. This is a divergence from Lucene’s Classic Query Parser.

Boosting a Term with "^"

Lucene/Solr provides the relevance level of matching documents based on the terms found. To boost a term use the caret symbol ^ with a boost factor (a number) at the end of the term you are searching. The higher the boost factor, the more relevant the term will be.

Boosting allows you to control the relevance of a document by boosting its term. For example, if you are searching for

"jakarta apache" and you want the term "jakarta" to be more relevant, you can boost it by adding the ^ symbol along with the boost factor immediately after the term. For example, you could type:

jakarta^4 apache

This will make documents with the term jakarta appear more relevant. You can also boost Phrase Terms as in the example:

"jakarta apache"^4 "Apache Lucene"

By default, the boost factor is 1. Although the boost factor must be positive, it can be less than 1 (for example, it could be 0.2).

Constant Score with "^="

Constant score queries are created with <query_clause>^=<score>, which sets the entire clause to the specified score for any documents matching that clause. This is desirable when you only care about matches for a particular clause and don’t want other relevancy factors such as term frequency (the number of times the term appears in the field) or inverse document frequency (a measure across the whole index for how rare a term is in a field).

Example:

(description:blue OR color:blue)^=1.0 text:shoes

The Boolean Operator "+"

The + symbol (also known as the "required" operator) requires that the term after the + symbol exist somewhere in a field in at least one document in order for the query to return a match.

For example, to search for documents that must contain "jakarta" and that may or may not contain "lucene," use the following query:

+jakarta lucene

The Boolean Operator AND ("&&")

The AND operator matches documents where both terms exist anywhere in the text of a single document. This is equivalent to an intersection using sets. The symbol && can be used in place of the word AND.

To search for documents that contain "jakarta apache" and "Apache Lucene," use either of the following queries:

"jakarta apache" AND "Apache Lucene"

"jakarta apache" && "Apache Lucene"

The Boolean Operator NOT ("!")

The NOT operator excludes documents that contain the term after NOT. This is equivalent to a difference using sets. The symbol ! can be used in place of the word NOT.

The following queries search for documents that contain the phrase "jakarta apache" but do not contain the phrase "Apache Lucene":

"jakarta apache" NOT "Apache Lucene"

"jakarta apache" ! "Apache Lucene"

The Boolean Operator "-"

The - symbol or "prohibit" operator excludes documents that contain the term after the - symbol.

For example, to search for documents that contain "jakarta apache" but not "Apache Lucene," use the following query:

"jakarta apache" -"Apache Lucene"

Escaping Special Characters

Solr gives the following characters special meaning when they appear in a query:

+ - && || ! ( ) { } [ ] ^ " ~ * ? : /

To make Solr interpret any of these characters literally, rather as a special character, precede the character with a backslash character \. For example, to search for (1+1):2 without having Solr interpret the plus sign and parentheses as special characters for formulating a sub-query with two terms, escape the characters by preceding each one with a backslash:

\(1\+1\)\:2

Grouping Clauses within a Field

To apply two or more Boolean operators to a single field in a search, group the Boolean clauses within parentheses. For example, the query below searches for a title field that contains both the word "return" and the phrase "pink panther":

title:(+return +"pink panther")

Specifying Dates and Times

Queries against date based fields must use the appropriate date formating. Queries for exact date values will require quoting or escaping since : is the parser syntax used to denote a field query: