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Relational databases as a tool to manage environmental data at the
research plot scale
Tyler EricksonInstitute of Arctic and Alpine Research
University of Colorado
Deborah DonahueData Manager, Snow Hydrology Research Group
Donald Bren School of Environmental Science and Management
University of California
Q: Why Relational Databases?
A: To Manage Large Data Sets
Storage Choices
• Field notes– Good for data
collection
– Difficult to share
Storage Choices
• Field notes • The bookshelf
Storage Choices
• Field notes
• The bookshelf• The file cabinet
Storage Choices
• Field notes
• The bookshelf• The file cabinet• Etc.
Distributable Storage Choices
• Text data files– Most flexible; easy to
set up & distribute– Difficult for analysis
Distributable Storage Choices
• Text data files• Spreadsheets
– Good for analysis– Inflexible distribution
Distributable Storage Choices
• Text data files• Spreadsheets• Database
– Best for large high-dimensional datasets; flexible distribution
– Work intensive to set up & maintain
Distributable Storage Choices
• Text data files• Spreadsheets• Database• GIS
– Best for spatial data– Uses a relational
database
It’s 4pm and you are somewhere near Granby, Colorado…
Do you know where your data are?
1 2 3 4
5 6 7 8
Data in Need of a Database
• Data Characteristics– Large volume– Constant format– Need for sharing
Designing a Database
Data Modeling1. Identifying related entities
• Sample locations, spatial extent, sampling methods, recorded data, data quality, topography…
2. Determining relationships between entities
Relationships
CARDINALITY: Defines the numeric relationships between occurrences of the entities
• One-to-One– (one member to one home address)
• One-to-Many– (one region/state/province to many members)
• Many-to-Many– (many members to many papers)
Example: Keeping Track of the WSC
Example Table Data
(MMSA Example)
Database Information System
Database Information System
Database Information System
Database Information System
Database Information System
Other Examples
• EPA
http://www.epa.gov/storet/
Other Examples
• EPA
• USGS Surface Water
http://waterdata.usgs.gov/nwis/sw
Other Examples
• EPA
• USGS Surface Water
• Snotel
http://www.wrcc.dri.edu/snotel.html
Summary
• Relational databases can be overkill for small data sets.
• Relational databases are a good choice for large data sets with a consistent format, that need to be distributed to many users.
Acknowledgments
• NASA-EOS
• Mammoth MountainEnergy Balance Monitoring Sitehttp://neige.bren.ucsb.edu/mmsa/