In the previous recipes, we have seen several type of queries that use text to match the results. The query string query is a special type of query that allows defining complex queries by mixing the field rules.
It uses the Lucene query parser to parse text to complex queries.
You need an up-and-running Elasticsearch installation as we described in the Downloading and installing Elasticsearch recipe in Chapter 2, Downloading and Setup.
To execute curl via the command line, you need to install curl for your operative system.
To correctly execute the following commands, you need an index populated with the chapter_05/populate_query.sh script available in the online code.
