4. Query and Retrieval of MapServer#

In this chapter, you will explore the query capabilities of MapServer and familiarize yourself with its Mapfile and template requirements. To gain knowledge of these capabilities, you will build a query application that uses most of the query power of MapServer.

The following sections describe the concepts necessary to understand the query process that operates on MapServer. Although the detailed usage and syntax are described, the function of this section is mainly as the main component of an overview.

Map browsing can only rely on MapServer to provide the basic functions of Web mapping services. In addition, MapServer also provides powerful spatial and attribute query functions.

In CGI mode, HTML templates are widely used to build queries and organize the information returned by queries, which usually involves complex interactions with map files, templates, and MapServerCGI programs.