The History of JavaScript and Databases

JavaScript and databases have a mixed history, due in part to JavaScript's success as the Web's scripting language. But the security provisions for Web applications has been to work in a "closed sandbox," which restricts the ability of a Web program to read (let alone write) local files. Here is the range of sandbox options:

• One can read a PC client's file, most often an image file, for upload to a website.
• One can write to a local cookie file addressed by name and date if the user permits cookies.
• Each cookie can be a maximum of 4K in length (including name and date ID).
• Your web server program may write a maximum of 20 cookies.

This is hardly the right stuff for database intensive applications; yet database operations take place in Web applications. But 99.99% of those database operations are done on a Web server. Or to be more precise, are passed on through the Web server to an application server which often invokes a database server. This 3-stage operation is the heart and soul of n-tier distributed Web processing that drives most current Web development. And JavaScript may be used either on the Web server or the application server and be involved in database operations.

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