Functional design

The following schematic diagram illustrates the functional design of SQLCat:

SQLCat Console

SQLCat Console is used for administrative access to SQLCat functions. It empowers the catalog author to do the following:

• Create hierarchical structures (e.g. customer's name, project name, etc.) under which catalogs can be imported
• Import catalogs produced with SPCat right from the Windows file system
• Create and administer user accounts
• Assign access rights for users or user groups on an object level

The console has been developed using Microsoft Visual Foxpro, just like SPCat.

SQLCat Database

SQLCat Database has been developed for MS SQL Server. It stores all catalog data:

• Parts lists
• Graphics
• Drawings
• Catalog configuration
• User accounts
• Security settings

It can be accessed from SQLCat Console as well as from SQLCat Application Server via an authenticated network connection using ODBC. In order to speed up complex operations, parts of the query logic are stored right on the SQL Server as "stored procedures". 

SQLCat Application Server

SQLCat Application Server has been developed for Microsoft Internet Information Server (IIS). The information stored in the SQLCat database is published by the application server via ASP pages (active server pages). In an ASP page, the application server establishes a connection to the SQLCat database. The data reqired for presentation are queried by the database server, processed in HTML, and then forwarded to SQLCat Frontend (web browser).

If the catalogs to be published contain confidential data, the entire communication (incl. transmission of catalog drawings) between web server and web browser can be performed encrypted via SSL. The performance of the overall application is only slightly reduced in this case.

In general, Application Server and Database Server can be installed on the same server (physically).

SQLCat Frontend (web browser)

SQLCat has been optimized for Microsoft Internet Explorer version 5 and later, but it will also work with most web browsers available today from other manufacturers.

The pages displayed to the catalog user in the frontend consist of ordinary HTML with embedded JavaScript. The display of the tree structure is based on a Java applet. The Java applet has been optimized for display of very complex and extensive tree structures. To this end, only data of currently visible parts are called from the application server during run time. This enables fast and convenient navigation with the mouse even in catalogs containing thousands of nods and hundreds of thousands of parts.