5.3 EXPANDDDL
Use EXPANDDDL
options to manipulate output for Enscribe record definitions containing arrays and redundant field names. This feature is primarily useful when mapping Enscribe files to SQL tables. It can also be useful when generating SQL tables based on Enscribe definitions using the DDLGEN
utility.
EXPANDDDL
is not necessary when the source database is NonStop SQL. If used, it must be the last argument entered.
Syntax
EXPANDDDLseparator
option
[, ...]
-
separator
-
A character separator for defining array output. See "Defining a separator".
-
option
-
For information about the options, see:
-
Information on inheriting
OCCURS
on "Inheriting OCCURS".
-
Defining a separator
Use separators for defining array output into columns. If any option besides NOEXPANSION
is specified, a distinct field is output for each occurrence of a given field and a grouping field with the original name.
For example, consider the DDL definition:
03 FIELDX PIC 9(5) OCCURS 2 TIMES.
Normally, the array is output as a single field with three occurrences. However, arrays do not exist in an SQL environment, so it may be desirable to create a column for each occurrence of FIELDX
. If the USEDASH
option is specified, the following fields are output:
FIELDX FIELDX-1 FIELDX-2
FIELDX
references all occurrences as a group item, while -1
and -2
are the individual occurrences.
If you are specifying a separator it must be the first option in the command string.
Default
USEDASH
Syntax
EXPANDDDL separator
separator
is one of the following.
Inheriting OCCURS
Use the EXPANDGROUPARRAYS
option to append indexes to fields that do not necessarily occur multiple times, but which are part of groups that occur multiple times.
Default
NOEXPANDGROUPARRAYS
Syntax
EXPANDDDL USEUNDERSCORE EXPANDGROUPARRAYS
Example
For the following definition:
03 A OCCURS 2 TIMES. 04 B PIC 9(5). 03 X OCCURS 4 TIMES. 04 Y PIC 9(5) OCCURS 4 TIMES.
B
within the second occurrence of A
becomes B_2
. The third occurrence of Y
within the fourth occurrence of X
becomes Y_4_3
.
Resolving duplicate field names
You can resolve duplicate file names by specifying a duplicate field option for:
-
Unique numerical index to the end of a duplicate field or column.
-
Unique alpha character index to the end of a duplicate field or column.
-
Group name at the beginning of a duplicate field or column.
Default
NORESOLVEDUPS
Syntax
EXPANDDDL dup_field_option
dup_field_option
is one of the following.
-
RESOLVEDUPINDEX
-
Appends a numerical index to the end of each duplicate field or column. For example,
END-DATE.YY
would becomeYY-2
in the output since it is the second occurrence ofYY
in the definition. -
RESOLVEDUPALPHAINDEX
-
Appends an alpha character index to the end of redundant fields or columns;
BEGIN-DATE.MM
would becomeMM-A
(occurrences are designatedA-Z
). -
RESOLVEDUPGROUP
-
Prefixes a duplicate field name with its group name and separator.
-
RESOLVEDUPFULLNAME
-
Use only when
RESOLVEDUPGROUP
cannot resolve duplicates.RESOLVEDUPFULLNAME
triggers the system to fully qualify the field name so that the redundancy is resolved. -
NORESOLVEDUPS
-
Do not resolve duplicate field names.
Examples
- Example 1
-
Consider the following definition.
03 BEGIN-DATE. 04 YY PIC 99. 04 MM PIC 99. 04 DD PIC 99. 03 END-DATE. 04 YY PIC 99. 04 MM PIC 99. 04 DD PIC 99.
BEGIN-DATE
andEND-DATE
duplicate theYY
,MM
andDD
field names. Normally these duplications would be resolved by referencing the higher level group item, such asBEGIN-DATE.DD
orEND-DATE.DD
. TheRESOLVEDUPGROUP
duplicate field option prefixes each duplicate field name with its group name, as inBEGIN-DATE-DD
andEND-DATE-DD
. - Example 2
-
In this example, the first non-redundant group above the elementary item is used for the prefix. For example,
END-DATE.DATE-DEF.YY
would becomeEND-DATE-YY
(DATE-DEF
is omitted).03 BEGIN-DATE. 04 DATE-DEF. 05 YY PIC 99. 05 MM PIC 99. 05 DD PIC 99. 03 END-DATE. 04 DATE-DEF. 05 YY PIC 99. 05 MM PIC 99. 05 DD PIC 99.
Omitting or including redefined fields
Use OMITREDEFS
or INCLUDEREDEFS
to omit or include redefined fields in the output definition. Including redefinitions has the following consequences.
-
DDLGEN
outputs a column for every elementary field item in the source definition, regardless of whether or not it redefines another field. -
When the Extract program specifies
FORMATASCII
orFORMATSQL
, the Collector outputs an ASCII field for each redefined field.
Default
OMITREDEFS
Syntax
EXPANDDDL [OMITREDEFS | INCLUDEREDEFS]
Fixing long field names
Use MAXCOLNAMELEN
to manage long field names. By default, the maximum field name length is 30. You can change this value with the MAXCOLNAMELEN
option.
When creating new field names to resolve duplicate occurrences, names occasionally exceed the length specified by MAXCOLNAMELEN
. When this happens, you are prompted for an alternative column name. To avoid the prompt, specify the NOFIXLONGNAMES
option after MAXCOLNAMELEN
.
MAXCOLNAMELEN
is invoked only with EXPANDGROUPARRAYS
or RESOLVEDUPGROUP
.
Default
FIXLONGNAMES
(prompt for an alternative column name)
Syntax
EXPANDDDL [MAXCOLNAMELEN length
| [NOFIXLONGNAMES]]
Altering field array display
Use ZEROFILL
to expand output definitions to a constant width, similar to:
EXPANDDDL USEUNDERSCORE ZEROFILL 3 EXPANDDDL USEUNDERSCORE ZEROFILL ARRAYWIDTH
Default
ZEROFILL
1
Syntax
EXPANDDDL {ZEROFILL width
} | {ARRAYWIDTH}
-
width
-
A value indicating the character width of the output.
-
ARRAYWIDTH
-
Specifies that the output width match the number of elements in the array.
- Example 1
-
If
ZEROFILL
ARRAYWIDTH
is specified for definition03 FLAG PIC X OCCURS 500 TIMES
, then occurrence 7 becomesFLAG-007
and occurrence 423 becomesFLAG
-423
. The width is equal to the occurrence frequency (500) and is three characters wide. - Example 2
-
Using the definition from the previous example and specifying
ZEROFILL
5
results in occurrence 7 becomingFLAG-00007
and occurrence 423 becomingFLAG-00423
.