Geographic Information Systems: An Introduction, 3rd Edition

18.5 Creating a Database

Creating a database is costly, time-consuming, and a drain on facilities and staff. Therefore, the databases employed in a GIS facility should be compiled as rapidly as possible so that the data they contain can be accessible as soon as possible. Consequently, both private firms and public agencies often arrange for data conversion and entry work to be done in round-the-clock shifts. Because they know their own data and professional fields, most organizations elect to convert and enter data in-house. As the workload involved may be enormous, outside temporary staff are often hired for the routine tasks.

Identified user needs, preferably ranked according to benefit-cost ratios, should determine the data entered in a database. Clearly, data accessed by many users have the greatest utility. Therefore, database creation should start with joint data. At the bottom of the data ranking list may be information entered on the premise that it may be useful at some time. In many cases, if its use is uncertain, it need not be entered.

The practical activities required will generally include the following:

• Development of templates if needed
• Thematic map manuscript preparation
• Digitizing and editing of objects
• Attribute coding and verification