Question

翻译2~~~~

1.3 Introduction to Spatial Data

Oracle Spatial is designed to make spatial data management easier and more

natural to users of location-enabled applications and Geographic Information

System (GIS) applications. Once this data is stored in an Oracle database, it can be

easily manipulated, retrieved, and related to all the other data stored in the

database.

A common example of spatial data can be seen in a road map. A road map is a

two-dimensional object that contains points, lines, and polygons that can represent

cities, roads, and political boundaries such as states or provinces. A road map is a

visualization of geographic information. The location of cities, roads, and political

boundaries that exist on the surface of the Earth are projected onto a

two-dimensional display or piece of paper, preserving the relative positions and

relative distances of the rendered objects.

The data that indicates the Earth location (latitude and longitude, or height and

depth) of these rendered objects is the spatial data. When the map is rendered, this

spatial data is used to project the locations of the objects on a two-dimensional piece

of paper. A GIS is often used to store, retrieve, and render this Earth-relative spatial

data.

Types of spatial data that can be stored using Spatial other than GIS data include

data from computer-aided design (CAD) and computer-aided manufacturing

(CAM) systems. Instead of operating on objects on a geographic scale, CAD/CAM

systems work on a smaller scale, such as for an automobile engine or printed circuit

boards.

The differences among these systems are only in the relative sizes of the data, not

the data’s complexity. The systems might all actually involve the same number of

data points. On a geographic scale, the location of a bridge can vary by a few tenths

of an inch without causing any noticeable problems to the road builders, whereas if

the diameter of an engine’s pistons are off by a few tenths of an inch, the engine will

not run. A printed circuit board is likely to have many thousands of objects etched

on its surface that are no bigger than the smallest detail shown on a road builder’s

blueprints.

These applications all store, retrieve, update, or query some collection of features

that have both nonspatial and spatial attributes. Examples of nonspatial attributes

are name, soil_type, landuse_classification, and part_number. The spatial attribute

is a coordinate geometry, or vector-based representation of the shape of the feature.
非自发自译~共9个问题1800分。。没有人会翻或者用工具翻我会关闭问题。。

Answer 1

我在怀疑是不是自问自答来领高分- -|||

Answer 2

9494我也觉得

Answer 3

天啊

Answer 4

9494