Subschema Declaration Attributes

Subschema declarations for DML and LRF subschemas contain the following attributes. Certain attributes are optional as explained in the following summary chart.

Attribute

Values can be:

SSCHEMA=

IDMS subschema name.

RELEASE=

nn.x (where nn is your release and x is your release version).

MODE=

LR or DML (DML is the default).

READY=

ALL or null or omit entirely.

DBNAME=

IDMS data source name from DBNAME table corresponding to its subschema. Used in local or CV mode. This attribute can be set dynamically. See Dynamically Setting the DBNAME and DICTNAME for information.

DICTNAME=

Secondary dictionary load area for CV mode only. This attribute can be set dynamically. See Dynamically Setting the DBNAME and DICTNAME for information.

NODE=

IDMS data dictionary table entry that identifies the DDS node location of an IDMS distributed database. For CV mode only.

DICTNODE=

IDMS data dictionary table entry that identifies the DDS node location of an IDMS distributed database subschema in a secondary dictionary load area. Use with CV mode only.

INDEXAREA=

Name of the integrated index area.

If your Master File defines record-types and LRF records from one or more IDMS subschemas, the Access File should contain one or more subschema declarations. After each subschema declaration, list its segment and index declarations. You must also specify the release of the IDMS software that was used in the last compilation of the subschema. Since MODE indicates the type of IDMS access the adapter performs, specify LR for LR records. DML is the default.

Another optional attribute is READY. Specify READY when an LRF record is built from two or more physical record-types located in several data source areas. The adapter prepares or readies all the areas of the subschema.

The DBNAME attribute is optional. Its value is the IDMS data source name from the DBNAME table that locates the real subschema name and location. This attribute supports multiple data source access. It can be used in local or CV mode to translate the subschema name into the proper load modules for data access.

If the subschema is not located in the primary dictionary or in a load PDS, use the DICTNAME attribute to identify a secondary dictionary load area. Remember that ASF subschemas are located in secondary dictionary load areas by default. So, if your Access File describes an ASF record, you must specify this attribute. Access Files containing this attribute are used in IDMS CV mode only.

The NODE attribute supports IDMS Distributed Database Systems. The value for NODE is the IDMS data dictionary table entry that identifies the DDS node location of an IDMS distributed database. This attribute is required only if DDS is installed at a user site and if the subschema and data source are located in a remote site location.

The DICTNODE attribute is similar to NODE, but DICTNODE supports secondary dictionaries in DDS environments. The value of DICTNODE is the IDMS data dictionary table entry that identifies the DDS node location of an IDMS distributed database subschema. DICTNODE is required only if DDS is installed at the user site and if the subschema and data source are located in a remote site location.

Note: When running using DDS, CV must be used because CA-IDMS does not support DDS access in local mode.


Information Builders