Definition
A spatial query is a special type of database query supported by spatial databases and geographic information systems (GIS). This type of query is specifically designed to work with data that is associated with spatial attributes like coordinates, polygons, and other geo-referenced details. Spatial queries provide the ability to specifically search for and analyze spatial data based on the spatial relationships instead of attribute or class.
What is Spatial Query?
In the context of GIS, a spatial query is a method of communication that allows the user to interact with geospatial data stored in a database. The fundamental function of a spatial query is to retrieve a particular subset of spatial data from within the database based on certain criteria. These criteria can be defined and manipulated by the user and may depend on spatial relationships such as containment, distance, intersection, adjacency, and others.
Spatial queries are a vital part of any spatial database system or GIS as they are the primary means of analyzing and utilising the spatial data. The spatial query is an incredibly powerful tool and is used in wide-ranging applications like urban planning, environmental studies, geography, transportation planning, and many others.
FAQs
What makes spatial query different from their non-spatial counterparts?
Spatial queries are different from non-spatial queries in that they consider the spatial location and nature of the data. For example, you may want to find all the buildings in a certain area, or find a road nearest to a certain location. Non-spatial queries, on the other hand, would deal with non-spatial data, such as the names of all students in a class or the salary of all employees in a company.
What kind of spatial relationships can be identified using spatial queries?
Many different types of spatial relationships can be queried using spatial queries. This may include containment (does A contain B), intersection (does A intersect B), proximity (what is near A), and adjacency (what is next to A).
What type of databases support spatial queries?
Spatial databases like PostGIS, Oracle Spatial, and other geo-databases support spatial queries. Additionally, Geographic Information Systems (GIS) software like QGIS, Atlas.co, and others have built-in capabilities to perform spatial queries on spatial data.
What are some practical applications of spatial queries?
Spatial queries are used across a broad range of disciplines including urban planning, environmental management, transportation planning, telecom and utilities networks management among others. They can be utilized in any field where location and geographical relationships are crucial.