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Databases serve a variety of functions, from simple means of data storage to analytical research tools. Consequently database design must take these different requirements into account. Most scientific researchers need both functions, but usually for specific (and limited) amounts and types of information (related to a defined research problem or series of experiments). The rapid expansion of desktop computing power has greatly facilitated database design.
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LEFT: Different types of database: the simple Flat File Database (basically analogous to a card index system), which is a single table of information; Relational Databases in which multiple tables of data are linked (related) such that queries can be asked of one or more in relation to data in another; GIS, which are relational databases accessable through maps (see Markwick & Lupia, 2002)
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For the Earth Sciences location in space and time is a crucial element of the data, and this is why desktop Geographic Information Systems (GIS) have become so widespread in the Geological community, as they place relational databases in the context of maps (GIS is used throughout all aspects of my research, presented in this site).
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| RIGHT: The basic design of many palaeontological databases comprises three principle tables: Locality (in time and space and which can include information pertinent to the spatial and temporal position of the fossil in question); Taxonomy (the taxonomic description of the fossil); Occurrence (providing the link between location and fossil name, which will be true for an occurrence of the fossil concerned). See Markwick & Lupia, 2002 for further discussion.
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The principle problem in geology is that the data is extremely heterogeous, and this creates many problems for database designers, and especially the unwarey database user who may naively assume that all data in a database is equal. This is dealt with in more depth in the data section. The deisgn must provide flexibiliy to account for this heterogeneity and in my databases this is accomplished with qualifying fields (attributes) that provide an indication of the grain (resolution) and condidence of data. In addition the Earth System Database includes numerous lookup tables (libraries) that make changes to the database easier to permeate through the whole system (see my PhD thesis for more details Markwick, 1996)
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LEFT: To the basic database structure are added lookup tables that allow for additions and changes to be more efficiently entered into the database structure and then permeated throughout the whole system.
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