Overview

An CA ADS application can access the CA IDMS/DB database by using navigational DML or SQL DML.

Navigational DML

CA ADS navigational DML is used to retrieve and update database or VSAM records and perform database control functions. Navigation DML commands can be used in process logic to store, retrieve, modify, and delete data in a non-SQL defined database, using a standard subschema or a Logical Record Facility (LRF) subschema.

When using LRF, the application developer selects a predefined path that meets the dialog's data requirements and codes simple database requests in dialog process logic. Database navigation is defined in the path, not in the process.

SQL DML

In an CA ADS application, SQL DML can be used to retrieve and update data defined with:

Records in non-SQL defined databases (associated with an SQL schema)
Tables in SQL-defined databases

Note: For more information about using SQL DML statements, see the CA IDMS SQL Self-Training Guide and the CA IDMS SQL Programming Guide.

Navigational DML and LRF commands used in the CA ADS environment are summarized in the following two tables. Documentation of command syntax appears later in this chapter.

Summary of Navigational DML Commands

Command	Purpose
ACCEPT	Moves database keys page information statistics from the database management system to a dialog
BIND PROCEDURE	Establishes communication from a dialog to a DBA-written procedure
COMMIT	Writes checkpoints to the journal file and releases locks held on database records
CONNECT	Connects member records to sets
DISCONNECT	Disconnects member records from sets
ERASE	Erases records from the database
FIND	Locates records in the database
GET	Copies record contents from the database to a dialog's record buffers
KEEP	Places locks on records
MODIFY	Replaces records in the database with the contents of a dialog's record buffers
OBTAIN	Locates records in the database and copies their contents to a dialog's record buffers
READY	Prepares database areas for processing
RETURN DB-KEY	Retrieves index entries without the associated record (used only with the Sequential Processing Facility and with system-owned indexed records)
ROLLBACK	Requests recovery of the database
STORE	Adds a record to the database

Summary of LRF Commands

Command	Purpose
ERASE	Deletes Logical Record Facility record occurrences
MODIFY	Changes field values in Logical Record Facility record occurrences
OBTAIN	Retrieves Logical Record Facility record occurrences
ON	Performs additional processing based on the outcome of conditional testing of Logical Record Facility record access
STORE	Stores a new occurrence of a Logical Record Facility record