Progress/400
Product Guide
The Server Schema
On the AS/400, a server schema (contained in a Dictionary Library) holds the file structure and schema information that the Progress/400 DataServer uses to translate between DB2/400 definitions and Progress/400 definitions. The Dictionary Library name of the server schema is the name by which the DataServer recognizes the DB2/400 database.
You determine which DB2/400 files serve as the basis of this DB2/400 database. For example, you can include a subset of files from one library and a subset from a second library into a single server schema.
The server schema contains a series of DB2/400 physical files, each with a P__ prefix, that correspond to DB2/400 database objects. The P__ files are similar to the Progress metaschema-they have a similar organization and contain the same kind of information. Table 1–1 lists the P__files contained in the server schema.
For example, the sever schema represents the DB2/400 physical file AS4CUST with four fields defined-cust-num, name, address, zip-by an entry for AS4CUST in P__FILE and by four entries in P__FIELD for cust-num, name, address, and zip.
The schema image contains the data definitions for the DB2/400 database like the schema definitions stored in a schema holder for a remote client. The Native 4GL Client and the Progress/400 AppServer use the schema image to map the data definitions in the server schema to a format Progress can understand. See "Preparing to Use AS/400-based Clients," for more information on creating the schema image.
Copyright © 2004 Progress Software Corporation www.progress.com Voice: (781) 280-4000 Fax: (781) 280-4095 |