Figure 5-1 demonstrates one scenario in which a PowerDynamo client connects to EAServer to process a PowerDynamo script, which contains a Methods As Stored Procedures (MASP) call to an EAServer component.
Figure 5-1: EAServer and PowerDynamo
These steps correspond to the numbers in Figure 5-1:
A browser requests a Web page. The Web page is a PowerDynamo script that contains HTML, SQL queries, and a MASP call to an EAServer component in that order.
The Web server passes the request to PowerDynamo.
The script is retrieved from the Web site (not shown in Figure 5-1). Processing of the script begins. The HTML and SQL queries within the PowerDynamo script are processed.
An ODBC or Open Client connection is made to a database to retrieve the necessary information for the SQL query.
The data is returned to PowerDynamo. Processing of the script continues until the EAServer component call is encountered.
Because a MASP call is being made, an ODBC or Open Client connection is made to access the EAServer component and the called method.
The component method is executed. If the method requires database access, a connection is made to a database to retrieve the appropriate data.
The data is returned to EAServer through an ODBC, Open Client, or JDBC connection.
The results from the EAServer function are returned to PowerDynamo through an ODBC or Open Client connection.
PowerDynamo passes the results, in HTML format, back to the Web server.
The results are passed back to the client through an HTTP connection.
EAServer and PowerDynamo can access several different databases; this diagram displays only one database.
EAServer components can access data from many different types of databases; you do not need a Sybase database to store data.
The client, PowerDynamo, and EAServer can all reside on either one machine or on separate machines.
A Web author can embed calls to EAServer components within a PowerDynamo script or template. The PowerDynamo script executes in the regular manner until it encounters the call to the EAServer component. At this point, a connection (through PowerDynamo) is made to EAServer, the appropriate method is executed, and the results are returned to PowerDynamo. PowerDynamo processes the information and returns HTML to the client.
