DATABASE DESIGN PRIMER A BEGINNERS GUIDE TO CREATING A DATABASE doc

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DATABASE DESIGN PRIMER A BEGINNERS GUIDE TO CREATING A DATABASE doc

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for Environmental Management of Military Lands CEMML Database Design Primer A Beginners Guide to Creating a Database By William Sprouse CEMML TPS 05-10 CENTER FOR ENVIRONMENTAL MANAGEMENT OF MILITARY LANDS Colorado State University Fort Collins, CO 80523-1490 June 2005 [...]... the amount of LCTA data an installation can collect let us look at an example Assume an installation with six years of data and an average of 224 plots/year recorded all of its' LCTA data using the standard LCTA paper forms (Tazik et al 1992) on single sided sheets After the sixth year of data collection a total of 42,822 pages would have accumulated This equates to 85.65 reams of paper or a stack... database a second check is needed to find any transcription errors In the next section data management tasks are discussed that will help facilitate the weekly data checks 5.1.1.3 Post Hoc Post hoc data management tasks are performed on data that is already in the database Most of the analyses for LCTA are based on the data that are found in the installation database, thus, this task is very important... the database concept, database software, and the knowledge of potential errors and their effect As more and more data is collected the task of data management becomes more intensive Once LCTA data is collected and uploaded to a database it is often hard to visualize just how much data an installation owns Megabytes mean little beyond the amount of disk space a file occupies To help add proportions to. .. or a stack of paper that would stand 14.27 feet Unfortunately there is no automatic tool that can be pointed at a data set and told to just "Fix" the data Data management starts before data collection, continues during data collection, and plays a large role after the data is collected Next LCTA data management is discussed 5.1.1 LCTA Data Management 5.1.1.1 A Priori One key process that reduces the... Earlier we defined the terms reliability and validity Internal validity is the ability to draw proper conclusions from a database This includes understanding the meaning of the data To truly understand the meaning of the data in a database you must understand the interpretation of the various measures within a database (variables) 5.2 Further Reading Refer to Chapter 5, Data Management, of the LCTA... studies of natural phenomena cannot be replicated because time is unidirectional This suggests that data management play a very important roll in the collection and analysis of ecological data LCTA depends heavily on the reliability and validity of its data However, LCTA has no well-defined organizational element charged with all aspects of data management, which can quickly become a serious and large function... physical database in Microsoft Access Data management is the next item to consider when dealing with databases Data management is beyond the scope of this document but a brief introduction specific to LCTA is presented below 5.1 Introduction to Data Management Data management is not a new concept Even Charles Babbage (1792-1871) recognized its importance over one hundred year ago Charles Babbage was commissioned... role in LCTA 10 Some of the driving factors that make data management of LCTA data an essential process of ITAM follow Insufficient quality control processes in the past have left many databases with incorrect data Errors during data collection are inherent to the data collection process Insufficient data management skills of the LCTA personnel have also led to incorrect data These include lack of knowledge... options, Cascade Update Related Fields and Cascade Delete Related Records, are optional Cascade Update Related Fields will automatically update the foreign key in the child table when the primary key in the parent table is changed For example, if the RecDate field of the PlotSurv table is changed the database will automatically change the corresponding data in the GndCover table (see Figure 12) Similarly,... methodologies are used create an installation LCTA inventory methods manual outlining all requirements Acceptable Codes In addition to vegetation codes much of the LCTA data utilizes codes Examples include military disturbance, basal cover categories, and vegetation condition The LCTA handheld data logger restricts the entry of data to only acceptable codes in most cases Be prepared for those instances when paper . database, and the type discussed here, is a relational database. A relational database is a collection of tables with relationships. A database is designed. for Environmental Management of Military Lands CEMML Database Design Primer A Beginners Guide to Creating a Database By William Sprouse CEMML TPS

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