Pathway/iTS TCP and Terminal Programming Guide

Designing Your Application

Compaq NonStop™ Pathway/iTS TCP and Terminal Programming Guide—426751-001

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Physical Design

You undertake the physical design of your database by selecting the appropriate file

types and record keys for each of the files in the database. Whether you are using the

Compaq NonStop™ Structured Query Language/MP (SQL/MP) software or the

Enscribe software as your database management system (DBMS), these file types can be

classified as key-sequenced, relative, entry-sequenced, or unstructured:

Although the file type you choose depends on your application requirements, generally

you should choose key-sequenced files for a database that will be accessed and

maintained by a Pathway application. Key-sequenced files provide more flexibility than

the other file types.

Database Managers

Databases supporting Pathway applications can run under either the NonStop™

SQL/MP relational database management system or the Enscribe database record

manager. Both of these products support the creation and use of large databases capable

of operating in local or distributed systems.

The NonStop™ SQL/MP product is both a database management system (DBMS) for

production environments and a relational database management system (RDBMS) for

decision-making in an information-center environment. The NonStop™ SQL/MP

product allows you to think about and represent files in the database as a collection of

similarly structured lists. For more information about designing NonStop™ SQL/MP

databases, refer to the Compaq NonStop™ SQL/MP Reference Manual.

The Enscribe database record manager provides a record-at-a-time interface between

Pathway servers and your database. For more information about designing Enscribe

databases, refer to the Enscribe Programmer’s Guide.

Key-Sequenced Each record in the file has a primary key and up to 255 alternate

keys. The primary key is a field or combination of fields within

the record.

Relative Each record in the file has a unique record number, which is the

primary key, and can have up to 255 alternate keys. The record

number is a unique value that corresponds to the physical location

of the record within the file.

Entry-Sequenced Each record in the file has a unique record number and can have

up to 255 alternate keys. The record number corresponds to the

order in which a record is stored in the file. The primary key is

the relative byte address of the record.

Unstructured Each record in the file has a unique record number that can be

used as the primary key. Alternate keys are not supported.