Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Oracle Database wikipedia , lookup
Entity–attribute–value model wikipedia , lookup
Extensible Storage Engine wikipedia , lookup
Microsoft Jet Database Engine wikipedia , lookup
Concurrency control wikipedia , lookup
ContactPoint wikipedia , lookup
Clusterpoint wikipedia , lookup
Relational databases as a tool to manage environmental data at the research plot scale Tyler Erickson Institute of Arctic and Alpine Research University of Colorado Deborah Donahue Data 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 highdimensional 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 Modeling 1. 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 Data File Database Information System Relational Database Data File Database Information System Relational Database Data File Database Client Tools Database Information System Relational Database Database Client Tools Data File Other Programs Pre-Processing Programs Database Information System Relational Database Database Client Tools Data File Other Programs Pre-Processing Programs Web Pages 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 Mountain Energy Balance Monitoring Site http://neige.bren.ucsb.edu/mmsa/