Summary

Database Connectors ensures that all changes to your database are immediately available to your COBOL program. Also, it ensures that all data updates introduced by your COBOL program are immediately reflected in the database.

After your XFDs have been generated, you can switch to a different RDBMS simply by setting DEFAULT_HOST to point to the new RDBMS. No recompiling is necessary.

Because Database Connectors accesses the database through its native engine, the full relational integrity of the database is maintained. The COBOL program need not be concerned about such things as enforcing relationships between keys and foreign keys on tables or constraints on field relationships and contents.

If you have specified that a file is to reside on a RDBMS by setting either DEFAULT_HOST or filename_HOST, an OPEN OUTPUT "filename" statement in your COBOL program will automatically generate a CREATE TABLE filename function on the specified host database. Appropriate permissions will be granted based on your login and password and on access parameters you have set. ( For details, see the "Contents" pane to find the appendix specific to your RDBMS.) If a table will eventually be large, you may wish to have your systems database administrator create the table and indexes for you. Databases offer many methods for creating tables that may improve performance for large tables, such as spreading the table across multiple hard drives or storing the data and the indexes on different drives.

Note: Database Connectors uses a specific naming convention for indexes it creates. Indexes created with Database Connectors use the i<TABLENAME>_<key value> convention. If you are using indexes created outside of the Database Connectors application, you must ensure that the index names match the Connectors naming convention.

Changes to the way a database functions should be carefully considered and tested before being fully implemented. If a database violation occurs, the engine detects it, and Database Connectors returns an I/O error condition to the COBOL program. The program can, if desired, call a standard COBOL library routine for an extended error description.

It is possible that there are library routines that do not work with or do not make sense to use with some of the Database Connectors interfaces. To find out if that is the case with your Database Connectors interface, look in the Common Questions and Answers section of the appendix specific to your interface.