spatial database: accomplishments and research needs
DESCRIPTION
Spatial Database: Accomplishments and Research Needs. presented by Fei Shen from S.Shekar,S.Chawla, S.Ravada,A.Fetterer, X.Liu,C.T.Lu EEE Transactions on Knowledge and Data Engineering 11(1): 45-55, 1999. Outline. Introduction & definition Spatial Database - PowerPoint PPT PresentationTRANSCRIPT
1Shen FEii
CSCI599-Fall2000CSCI599-Fall2000
Spatial Database: Accomplishments and Research
Needs
presented by Fei Shen
from
S.Shekar,S.Chawla, S.Ravada,A.Fetterer, X.Liu,C.T.Lu
EEE Transactions on Knowledge and Data Engineering 11(1): 45-55, 1999
2Shen FEii
CSCI599-Fall2000CSCI599-Fall2000 Outline
Introduction & definition• Spatial Database
• Related Work and Authors’ Contribution
• Scope and Outline
Accomplishments
Research Needs
Summary and Discussion
3Shen FEii
CSCI599-Fall2000CSCI599-Fall2000
Introduction
4Shen FEii
CSCI599-Fall2000CSCI599-Fall2000Introduction: Spatial Database
DEF: Efficient and Effective management of data related to a space Physical World, e.g. geography, urban planning,
astronomy Engineering Design, e.g. VLSI circuits design,
design of automobile Conceptual Information Space, e.g. multi-
dimension support system, fluid flow, electro-magnetic field
Existing Application Geographic Information System Computer Aid Design
5Shen FEii
CSCI599-Fall2000CSCI599-Fall2000 Spatial Database (cont’d)
Existing Application Multimedia Information System
Data Warehousing
NASA Earth Observation System
Commercial Examples Informix’s Spatial Data Blade
Oracle’s Universal Server with Spatial Data
ESRI’s Spatial Data Engine
6Shen FEii
CSCI599-Fall2000CSCI599-Fall2000 Related Work
Won Kim SSD 93 Research Direction
• Validation of relative performance• Query Optimization for spatial queries• Cost Model• Extensible Data Structure and Spatial Operations• Object Oriented Paradigm
Guting VLDB 1994 Survey and Classification
• Spatial Data System• Spatial Data Model• Spatial Query Language• Spatial Indexing• Spatial Join Methods
7Shen FEii
CSCI599-Fall2000CSCI599-Fall2000 Authors’ Contribution
Authors’ Contribution Identify Recent Accomplishment
Current Research needs
8Shen FEii
CSCI599-Fall2000CSCI599-Fall2000 Scope and Outline
Object-relational Databases Spatial Data Types Spatial Operations Multi-Dimensional Indexing
Three Layer Architecture Object Relational Database Management
system Spatial Database Spatial Application
• GIS, MIIS
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Three Layer Architecture
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CSCI599-Fall2000CSCI599-Fall2000
Accomplishments
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Accomplishments: Space Taxonomy
Set Base Space Formalize the set relationship
Relational and Object-relational DB uses this model of space
Topological Space Basic Concept: Neighbor
GIS Operation: overlap, adjacent
Network Space Basic Concepts: graphs, nodes, edge, connectivity
GIS Operation: connected, path
12Shen FEii
CSCI599-Fall2000CSCI599-Fall2000 Space Taxonomy…
Euclidian Coordinatized Space Basic Concepts: coordinate system
GIS Operation: North of, South of
Metric Space Formalize the distance relationships
13Shen FEii
CSCI599-Fall2000CSCI599-Fall2000
Rpresentative Function Specified by OGIS …
14Shen FEii
CSCI599-Fall2000CSCI599-Fall2000 A Sample of Spatial Operations
15Shen FEii
CSCI599-Fall2000CSCI599-Fall2000Accomplishments: Spatial Data
Model
Data Abstraction: hides the details of data storage
Field-based Model Transform a space partition to an attribute
domain Local, focal, zonal operations
Object-based Model Information Space populated by discrete,
identifiable, spatially referenced entity Distance and Boundary operations
16Shen FEii
CSCI599-Fall2000CSCI599-Fall2000Spatial Data Type Hierarchy by
OGIS
17Shen FEii
CSCI599-Fall2000CSCI599-Fall2000Accomplishments:Spatial
Querying
Efficient Representation Object Model
Spaghetti Model
Node-arc-area Model(NAA) model
Double-connected-edge-list (DCEL)
Boundary Representation, Field Based Model
Tessellation
Triangular irregular networks (TIN)
18Shen FEii
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Spatial Querying …
Efficient Algorithm Filter and refine algorithm
1. Filter: returns a set of candidate object which is a superset of the objects fulfilling a predicate
2. Refine: for each candidate, the exact geometry is checked
Plane sweeping algorithm
Spatial join- nested loop, tree matching space partitioning, join-index
19Shen FEii
CSCI599-Fall2000CSCI599-Fall2000Query Example
Example Find all lakes which have an area greater than 5 sq. km. And
within 20 km. From campground
20Shen FEii
CSCI599-Fall2000CSCI599-Fall2000 Figures for Spatial Query
21Shen FEii
CSCI599-Fall2000CSCI599-Fall2000
Accomplishments: Spatial File Organization and Indices
Space Filling Curve Clustering
Metric Clustering Technique Topological Clustering Technique-CCAM
Spatial Indices for point objects Grid Files, Point-Quad-Tree, KD-tree
Spatial Indices for extended object R-tree, Field tree, Cell tree BSP tree, Balanced and Nested Grid Files
22Shen FEii
CSCI599-Fall2000CSCI599-Fall2000 R-Tree
Height balanced extension of B+ tree Objects are represented by MBR
23Shen FEii
CSCI599-Fall2000CSCI599-Fall2000 Other Accomplishments
File design for storage on tertiary storage device Juke boxes
Declustering Method
Dynamic-load balancing techniques Multi-dimensional spatial data
Hierarchical algorithm Shortest path computation
View materialization
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Research Needs
25Shen FEii
CSCI599-Fall2000CSCI599-Fall2000Research Needs: Space
Taxonomy
A sequence of operations on discretized data
Lead to growing errors
Formalize the discetization process
Formalize the associated errors
Formalized the interpolation E.g. estimate the characteristics of terrain or
ecological conditions from a limited number of field measurements.
26Shen FEii
CSCI599-Fall2000CSCI599-Fall2000
Research Needs: Spatial Data Model
Network Space Data Model
Data Types• Node , edge, path
Kernel set of operations• Get successor, shortest path
Field data model toward field based query language
27Shen FEii
CSCI599-Fall2000CSCI599-Fall2000
Research Needs: Spatial Query Processing
Query Cost Modeling Selectivity of Spatial Search
Selectivity of Join Operation
Strategy for bulk loading
Query related to fields and networks
28Shen FEii
CSCI599-Fall2000CSCI599-Fall2000
Difficult Spatial Queries From GIS
Buffer Find the areas 500ft. From power lines
Voronoize Classify households as two which supermarket they are closet to
Neighborhood Determine slope based on elevation
Network Find the shortest path from warehouse to all delivery stops
Allocation Where is the best place to build a restaurant
Transformation Triangulate a layer based on elevation
Bulk Load Load a spatial data file into the database
Raster->vector Convert between raster and vector representation
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Example of Spatial Query Processing
Logical Transformation May not always applicable in spatial database
30Shen FEii
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Research Needs: Spatial File Oragnization and Indices:
Physical Leverl
Network Space File Clustering Indices Characterized Access Pattern Design Access Methods
Concurrency Control R-link tree for R-tree Other Spatial Indicies
Data Volume NASA’s EOS
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Research Needs: Other
Benchmark Earth Science: Sequoia 2000 GIS DWH Transportation
Work Flow Modeling Concurrency Control Recovery and Backup Visual Presentation
Graphic Images 3D displays Animation
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CSCI599-Fall2000CSCI599-Fall2000
Summary and Discussion
33Shen FEii
CSCI599-Fall2000CSCI599-Fall2000Summary and Discussion
Research needs with few publications Spatial graphs Filed based modeling Cost modeling Concurrency control for query processing Discretization for error propagation
Large number of publication Object-based data modeling Spatial data types Filter and Refine techniques for query processing Spatial Indexing
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More Spatial Application
GIS, CAD, EOS
Multimedia: Text, Audio, and Video
Web Data
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Recent Research in Spatial Database