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EXTRACT (EX)
$ As logic associated with a Frame is performed when the Frame is extracted, a Frame
cannot be extracted from within its own logic. If a Frame is extracted for use in
another Report, the Frames should be defined identically in both Reports.
$ See ‘‘Numeric Data Items in Extract Files’’, later in this section for further details.
To create an Extract file for MAPPER you must create an Extract file in Report Frame
format. In MAPPER Extract files, the columns of data values are separated by tabs.
Numeric Data Items in Extract Files
For numeric data items in Extract files:
$ Numeric data items extracted as part of a Frame may have a different format from
those extracted as part of an Ispec record (depending on the host type). The default
for Frame numeric data items is COBOL type DISPLAY. This can be changed to COMP
by adding the BCD Data Attribute to the data item. Ispec numerics are always COMP.
$ Numeric data items extracted as part of an Ispec record are extracted as COMP for
MCP based LINC Systems, COMP-3 for UNIX, and DISPLAY for OS 2200 based LINC
Systems. See the COBOL Manual for implications of signed points.
$ Numeric data items extracted as part of a Frame have the sign folded into the least
significant digit. See your COBOL manual for a description of the PICTURE clause for
details on folding the sign in.
$ For MAPPER Extract files, numeric data items must have leading signs. To achieve
this, define the relevant numeric data items with the FLOATING.SIGN Data Attribute.
Multiple Extracts to the Same File
If an Extract file has already been accessed by another command, such as a DETERMINE;
ACTUAL or SORT; command, the EXTRACT; command will append data to the existing
file, unless the RESTART; command is used.
If you Extract multiple Frames that include the same data item (from the same Ispec) to an
Extract file, and then read this item back in, you will receive a COBOL error or warning,
and your Reports may not function as intended.
LINC does not distinguish the same data item extracted to the same file from different
Frames when that file is read back in.
For example, you may have an Ispec data item CUST.NAME painted in both Frames 10 and
11, and you extract both these Frames to file A. A later DETERMINE; ACTUAL A
EXTRACTED.AS; 10 and a reference to A*CUST.NAME will refer to Extract file records
extracted from both Frame 10 and 11.
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