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<br />~'I '....\ <br /> <br />OUO~J3 <br /> <br />.' <br /> <br />South Platte Water Rights Management System <br /> <br />1.0 Introduction <br /> <br />This manual contains information on the underlying structure of the South Platte Water <br />Rights Management System Database. It is intended to give the database developer <br />enough background in the structure of the database to be able to maintain and enhance it. <br />The following aspects of tbe SPWRMS database will be discussed: <br /> <br />. SPWRMS database data model, <br />. Relational database description, <br />. Maintaining the relational database, <br />. Spatial database description, and <br />. Maintaining the spatial database. <br /> <br />1,1 SPWRMS Data Model <br /> <br />All of the data tbat are needed in SPWRMS database have three unique characteristics. <br />First, all of the data have a spatial location. Second, many of these spatial features have <br />important spatial relationships (e.g., relationships between upstream and downstream <br />features in a river network). Third, all of the features have a temporal dimension which is <br />sometimes recorded (i.e., a stream gauge has a history of flows). The SPWRMS database <br />is built on a data model thar is capable of effectively managing all of these characteristics. <br /> <br />The geo-relational data model is a hybrid model that is based on coupling the plane <br />topology data model and the relational data model. Location data and the relationships <br />between the locations is managed in the plane topology model. Information describing <br />characteristics of the location data is managed in the relational model. There are several <br />commercial geographic information systems available that are based on this model. <br /> <br />The data managed by the plane topology model is composed of coordinates and relation- <br />ships between features that the coordinates form. For example, a hypothetical reach of <br />river might be described as a line (i.e., river) which is defined by a series of coordinates. <br />The line has a starting point (i.e., start node). an ending point (i.e., end node). and a unique <br />rD. The start node might represent a stream gauge; the end node might represent a dam; <br />and the unique ID of the line represents a specific river (i.e., main stem of the South Platte <br />River). Moreover, the direction of the line indicates the direction of flow. Another reach of <br />river might then be defined by a series of coordinates whose starting node is the ending <br />node of the previous line, etc. <br /> <br />The relational model can be thought of in terms of tabular information, where each table <br />holds attribute values for a certain type of entity. The data table is in row-column format <br />with columns representing different entity attributes, and rows storing data for specific <br />instances of entities; e.g., a specific stream gauge. Building on our last example, a stream <br />gauge which is described as a node in the plane topology model, has several attributes: a <br />unique ID, a hydraulic height, a history of storage in the reservoir behind it, etc. The flow <br />data might be stored in a table, with other physical characteristics of the stream gauge, <br />which would have a column for stream gauge ID, name, and 8-character name abbrevia- <br />tion. Each row in the table would hold a unique stream gauge ID which would be the same <br /> <br />Database Manual <br />