# The Filter Editor

The main window's list of files and a database's rows can be filtered. This topic describes the filter editor ... not the particulars of the specific filter control usages.

An appropriate filter editor can be displayed via the Edit>Find>Find... menu item or even better by its typical Command-F shortcut.

Filters are used to determine which items match or do not match a set of specified rules. Saved filters are available within a filter editor and from appropriate context menu items to perform specific actions with the results of a filter.

There are three types of items displayed in the filter editor:

Compound
  Compound items contain others. There are three types of compound items. Those that require that no contained items match (None); those that require that at least one contained item matches (Any) and those that require that all contained items match (All). Compound items are added by clicking on a button with the four horizontal lines.
Summary
  A summary item describes a single test condition. New summary items are added by clicking on a + button.
Configuration
  Every Summary item contains a single configuration item. In configuration items you choose fields, operators and choose or specify values.

The first button in a Configuration item is the field selector. The field defines which metadata you are interested in.

Filter operators are divided into the following classes: Text, Integer, Decimal and Boolean. Most fields which can be filtered use a default operator class but they can choose any of the operators in any class. Text operator are described using text. Integer operators use ==, !=, <, etc. In order to differentiate decimal operators from integer operators they are preceded with a period. eg. .==, .!=. .<, etc. Boolean operators are True or False.

The numeric and text based operators require you to specify a value that you are attempting to match. The value field may contain escape sequences inserted via the field's context menu. It is though this extensibility that you can compare selected fields against others.

The text is like operator supports the * (match 0 or more) and ? (match 1) wildcard characters. Unless you want your pattern to be anchored on the right make sure you specify a trailing *.

The text regular expression operator only pre-processes the following escape sequences: \L (disable escape sequence processing) and items which insert content dependent on where the filter editor is activated. All other escape sequences are assumed to be regular expression escape sequences. You can test a regular extension in the Regular Expression Tester.

The disclosure button at the lower left of the window displays a menu which can display the following functions. (Note that the filter control's context menu has the same functions):

Expand All
  Expand all items in the control.
Collapse All
  Collapse all items in the control.
Show Outline
  All compound items are expanded displaying summary information. Configuration items are collapsed.
Save Filter
  Allows you to name and save a filter which can be used on Close Files, Hide Files and Select Files menus. File>Save and the Command-S keyboard shortcut accesses the same function.
Reset Filter
  Clearing a large filter can be tedious. This is a convenience method to clear a filter.
Load Saved Filter
  Allows you to load a saved filter from a list displayed on a menu.
Delete Saved Filters
  Displays a panel allowing you to delete saved filters.
Grid Style
  Allows you to pick a grid style of None, Dashed or Solid.
Expand All when Loading
  Allows you to control how filters are expanded when loaded. You can essentially automatically do an Expand All (green indicator) or Show Outline (dim indicator).

The Cancel button will close the panel without applying the displayed filter. The displayed filter will be preserved.

Additional Information:

Main Window Filters

Database Filters