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EXTRACT (EX)
EXTRACT (EX)
The EXTRACT; command puts the current values of data items from selected Component,
Event, or Report Frame records into an Extract file.
An Extract file can be read by:
$ The same Report that created it
$ Another Report within your LINC system
$ Another LINC System (on the same host or on a different host)
$ A standalone program (which may read the data into a non-LINC system)
$ MAPPER (by specifying the MAPPER; command option with an EXTRACT; command)
When using Extract files, consider the following points:
$ Up to 26 simultaneous Extract files can be created in a Report.
$ Multiple extracts involving the same Extract file append to the file. For more details,
see ‘‘Multiple Extracts to the Same File’’, later in this section.
$ On OS 2200 based LINC Systems, the Extract file is opened when the first EXTRACT;
command is executed, and is closed when the Report terminates. Therefore the data
items defined in the Extract file will not be available until the EXTRACT; command is
actually executed. Using data items defined in the Extract file when the file has not
been opened will cause a runtime error (in UCS). Therefore, if the EXTRACT;
command is executed conditionally, use of the data items should also be conditional.
$ In LDA Run Time, the PACKED BINARY and TAPE options are not implemented. The
location of the extract files is determined by the Extract path field in the Report
Options dialog box.
$ To close the current Extract file and open another one, use the SET.TITLE; command.
$ When switching from reading an Extract file to appending data to it, the first
EXTRACT; command should be immediately followed by a CRITICAL.POINT;
command. Failure to do this could result in duplicate records on the Extract file if the
Report was aborted and automatically recovered at this point.
Caution (OS 2200 based LINC Systems)
On OS 2200 based runtime hosts, a maximum of 60,000 tracks will be allocated
to your Extract file, as the default. If you envisage your file being larger than this,
catalog the file prior to running the Report. You can increase this maximum by
using the file size option within @CAT. If you pre-catalog an Extract file, it must be a
permanent file.
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