Query parameters are an important aspect of using Apache Solr to search for information. Here’s a brief overview of the most commonly used query parameters in Solr:
1. “q”: The “q” parameter is the most important query parameter in Solr, as it specifies the search query to execute. For example, to search for documents that contain the word “Solr”, you would use the following URL:
http://localhost:8983/solr/yourcore/select?q=Solr
2. “start” and “rows”: The “start” and “rows” parameters are used to implement pagination in Solr. The “start” parameter specifies the offset of the first result to return, while the “rows” parameter specifies the maximum number of results to return. For example, to get the second page of search results (with 10 results per page), you would use the following URL:
http://localhost:8983/solr/yourcore/select?q=Solr&start=10&rows=10
3. “sort”: The “sort” parameter is used to specify the sorting order of search results. You can sort by one or more fields, and specify the direction of the sort (ascending or descending). For example, to sort search results by relevance, you would use the following URL:
http://localhost:8983/solr/yourcore/select?q=Solr&sort=score desc
4. “fq”: The “fq” parameter is used to apply filters to search results. Filters are similar to queries, but are used to limit the set of documents that are returned. For example, to search for documents that contain the word “Solr” and have a “category” field with the value “books”, you would use the following URL:
http://localhost:8983/solr/yourcore/select?q=Solr&fq=category:books
5. “fl”: The “fl” parameter is used to specify which fields should be returned in search results. By default, Solr will return all fields in the index. However, you can specify a subset of fields to return using the “fl” parameter. For example, to return only the “title” and “description” fields, you would use the following URL:
http://localhost:8983/solr/yourcore/select?q=Solr&fl=title,description
These are just a few examples of the query parameters in Solr. Solr provides a wide range of query parameters that can be used to customize and fine-tune your search queries. The Solr documentation provides detailed information on all of the available query parameters and how to use them for your specific use case.