A filter on one or more columns reduces data that is not needed or wanted in reports based on the Domain. For example, financial reports for the current fiscal year may need data from the previous fiscal year for comparison, but nothing earlier. It is always good practice to filter out irrelevant data to reduce the size of query results and processing time within the server.
Also, reports based directly on the Domain can define their own filters. Putting often-used filters in the Domain design avoids the need for each user to define filters independently and also reduces the chance for errors.
You can define a filter on a column that you do not plan to expose in the Domain. The filter remains active and only data that satisfies all defined filters appears to report users. For example, you can filter data to select a single country, in which case it doesn’t make sense for the column to appear in a report. However, you should clearly document such data restrictions in the description of the Domain, so that users understand what data is accessible through the Domain.
To define a filter:
| 1. | Double-click a column in Fields. |
Alternatively, you can drag a column to the Filters panel. The column appears in the Filters panel with a list of conditional operators you can apply to that column.
| 2. | Choose the comparison operator and filter value from the drop-down. |
In the Filters panel, the choice of comparison operators depends on the datatype of the column. For example, string types offer a choice of string search operators and date types offer time comparison operators. The filter value depends on the datatype and the comparison operator.
For example, if you select a date column with the is between operator, the Filters panel displays two calendar icons for specifying a date range:
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Filters Panel of the Domain Designer |
Text columns have both substring comparison operators such as starts with or contains and whole string matching such as equals or is one of. When you select a whole string matching operator, the panel displays a list of all existing values for the chosen column, retrieved in real-time from the database. If there are more than 50 values to display, use the search controls to the left and click 
to narrow the list of available values. For multiple value matching, double-click the available values to select them. You may perform multiple searches and select values from each list of results.
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To define a filter that compares two columns of the same datatype, Ctrl-click to select the second column, and drag the columns to the Filters panel. This action is possible only when two columns of the same type are selected. |
| 3. | Click OK to define the filter. To clear the condition editor without saving a filter, click Cancel. |
Filters shows all the filters you have defined. The overall filter applied to the data is the logical AND of all conditions you defined.
In Filters, click Change to modify a filter you defined. Click OK to save the changes. After selecting a row, you can click the Remove button to remove it from the list.
