Accessing a database – Adobe Dreamweaver CS3 User Manual
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DREAMWEAVER CS3
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A. Step 1 - Web browser requests dynamic page. B. Step 2 - Web server finds page and passes it to application server. C. Step 3- Application
server scans page for instructions and finishes page.
D. Step 4- Application server passes finished page back to web server E. Step 5 - Web
server sends finished page to requesting browser
Accessing a database
An application server lets you work with server-side resources such as databases. For example, a dynamic page may
instruct the application server to extract data from a database and insert it into the page’s HTML. For more infor-
mation, see
The instruction to extract data from a database is called a database query. A query consists of search criteria
expressed in a database language called SQL (Structured Query Language). The SQL query is written into the page’s
server-side scripts or tags.
An application server cannot communicate directly with a database because the database’s proprietary format
renders the data undecipherable in much the same way that a Microsoft Word document opened in Notepad or
BBEdit may be undecipherable. The application server can communicate with the database only through the inter-
mediary of a database driver: software that acts like an interpreter between the application server and the database.
After the driver establishes communication, the query is executed against the database and a recordset is created. A
recordset is a set of data extracted from one or more tables in a database. The recordset is returned to the application
server, which uses the data to complete the page.
Here’s a simple database query written in SQL:
SELECT lastname, firstname, fitpoints
FROM employees
This statement creates a three-column recordset and fills it with rows containing the last name, first name, and fitness
points of all employees in the database. For more information, see
The following example shows the process of querying a database and returning data to the browser:
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September 4, 2007