Applying a filter to the current data file enables you to limit the amount of records that are displayed at a time.
Your filter is defined by one or more sets of conditions, and you can produce filtered results that include or exclude records
matching all or any one of those sets.
There are two types of condition that you can use within each set:
- Reference condition
- A reference condition uses the same principles as reference modification in your COBOL syntax. You specify the starting position
within a record in which to start filtering, and then specify the number of positions on from that in which to filter; for
example, values of 7:3 will filter on positions 7 to 9 within each record, as indicated below
- Field condition
- This type of condition is only available if you have applied a layout to your data file. A field condition allows you to select
a field name from the layout instead of having to manually specify a start and end position on which to base your filter.
You can select any non-group field in the layout.
For both types of condition, you select an appropriate data type, an operator (for example, greater than, contains, or not
equal to), and a value that you wish to filter on.
Data File Editor retains the last set of filtered results until another filter is applied, which enables you to toggle between displaying
these results and displaying the original data file.
Note about remote filtering: When dealing with data files on a remote Fileshare server (see
Opening a Data Set in Enterprise Server), there may be performance differences depending on the version of the server. Product versions from 5.0PU13 or 6.0PU3 onwards
support server-side filtering, which performs the filtering on the remote server, and then only returns the filtered records
to the client: this significantly improves performance. Filtering files using a Fileshare server older than this results in
all records being downloaded locally before being filtered.
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There is also a deprecated filtering function from earlier versions of the editor. It is currently available because it contains
some functionality not yet available in the new version. As the new version matures, the older version may be removed.