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Vector Spatial Relationship and Spatial Querry


Spatial relationships show how things are located in relation to each other on a map.

Here are some examples:

Relationship TypeExample
NearA school is near a hospital
InsideA tree is inside a park
TouchingTwo countries are touching at their borders
OverlappingA flood zone overlaps with farmland
ConnectedOne road is connected to another road

Spatial Query?

A spatial query is a question that asks about the location or relationship between features on a map.

It's different from a regular query (which asks about data in a table).
A spatial query asks about where things are and how they relate to each other.

Examples of Spatial Queries:

  1. "Which schools are within 1 km of the main road?"

  2. "Find all rivers that cross the highway."

  3. "Show all houses inside the flood zone."

  4. "Which villages are near a hospital?"

GIS uses this information to highlight or select features based on their spatial relationships.

 Why is this Important?

  • Helps in planning (e.g., where to build a new fire station)

  • Helps in disaster management (e.g., find houses inside a danger zone)

  • Helps in research (e.g., see which farmlands are near rivers)

 Summary

TermSimple Meaning
Vector DataMap data made of points, lines, and areas
Spatial RelationshipHow map features are related in space (near, inside, touching, etc.)
Spatial QueryAsking questions based on location, like "What is near this?"


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