Data is collected in Qualtrics and exported to Excel. Data is screened for quality then imported to an MS-Access database. The online application is written in ASP.NET. To keep maintenance to a minimum the application is primarily driven by the database. All maps, charts, and queries are written in SQL contained and described in the database. Charts and Maps are rendered using Google Charts driven by SQL queries from the database. New data, charts, maps, and queries are maintained using the Access desktop application then the database is simply uploaded to the web site to update the online application.
Due to the nature of the data collection not every state or institution reports every year and states may not report completed data. Each data record contains validity flags for each portion of the data. These flags are used to filter data in the SQL queries. For a simple query such as total teachers only a single flag may be used. For queries requiring calculation such as the "demand metric" flags for each component will be used. This will result in a differing number of records being returned since a state may report some but not all data. Note that "all data" queries are not filtered.
Questions about the site can be addressed to Michael Spiess (California State University, Chico)
