The interface view engine always reads in the
CA-DATADICTIONARY information when it processes a view descriptor. The reason is that
CA-DATADICTIONARY contains information that is not in the view descriptor, such as the
element entity.
Consider the following
matters regarding
CA-DATADICTIONARY usage by the interface view engine:
-
Elements are groupings of fields. They are used to read and update the tables. The
interface view engine makes a "best-fit" list of elements to use when it executes
the view descriptor. If the
database administrator fine-tunes the element definitions to improve performance, the interface
view engine can take advantage
of the improvements.
-
The interface view engine rejects a view descriptor if certain information that is
stored in the view descriptor does not match the dictionary. Specifically, you cannot
change the following
information:
-
entity-occurrence names and types for these entities: DATABASE, FILE, RECORD, KEY, FIELD
-
field class, from simple to compound or vice versa
-
field data types, from one category to another. The categories are as follows:
-
numeric: types
B (binary), 2 (halfword), 4 (fullword), 8 (double), N(Zoned), D (packed
decimal)
-
float:
types L (long float), S (short float)
-
alpha:
types C (char), H (hex)
-
Xtype:
types B > 8 bytes, D and N > 16 bytes, E (extended float), G
(graphics), K (kanji), T (PL/1 bit), Y (double byte character set),
Z (mixed DBCS and single byte)
Note: Xtype is an artificial type.
It represents a CA-Datacom/DB
type that cannot be fully handled in SAS.
-
You should set up a CA-DATADICTIONARY user ID and password for SAS and not change
them. The user ID should have retrieval authority in CA-DATADICTIONARY for six entity-types:
DATABASE, FILE, RECORD, ELEMENT, KEY, and FIELD. The user ID and password do not protect
data, but the interface view engine needs them to obtain information from CA-DATADICTIONARY.
If you change the user
ID or password, then the view descriptors must be re-created, or you must use the
data set options to override the user ID and password. (You can also zap these values
in
the CSECT DDBAUSE option, which is used by the ACCESS procedure.)