Query Window

Query Window: Rows Tab

The Rows tab displays a list of filters used in the current query.  If the query is a custom query and not read-only, filters can be added, edited or deleted on this tab.

Filters are used to select which records appear in the result set. Filters can have 4 kinds of basic condition. These are:

• Add If
• Add Unless
• Exclude If
• Exclude Unless

When Family Historian runs a query it applies all the filters to decide which rows will be included in the result set. If the first filter is 'Add If' or 'Add Unless' it initially makes the result set empty. If the first filter is 'Exclude If' or 'Exclude Unless' it initially puts all records (of the type used by the query) in the result set. Then it applies each filter sequentially to the result set, as follows:

• For each 'Add If' filter it adds to the result set any records which match the condition of the filter.
• For each 'Add Unless' filter it adds to the result set any records which do not match the condition of the filter.
• For each 'Exclude If' filter it removes from the result set any result set records which match the condition of the filter.
• For each 'Exclude Unless' filter it removes from the result set any result set records which do not match the condition of the filter.

After all filters have been applied in turn, whatever records are left in the result set are displayed in the Result Set tab of the Query Window.

General filters (General tab) use an expression - that is, either a data reference (see Understanding Data References) or a function (see Understanding Functions) - and compare its value against a value specified in the filter.  Expressions can be as complex as you like.  If you want to create complex and/or conditions, for example, you can do this with expressions.

Relations filters (Relations tab) are used to check relationship conditions - such as whether a given Individual is a relative of a specified type of anyone who is already in the result set.

List filters (List tab) are a convenient way of checking membership of Named Lists (see How to Use Named Lists).

Filters can be added or updated using the Add and Update buttons in the bottom right corner of the Query Window. They can be deleted by clicking on the the Delete button , or re-ordered by clicking on the Move Up and Move Down buttons , at the bottom-left corner of the filter list.

Disabling and Re-Enabling Row Filters

Sometimes, if filters do not produce the results you expected, it can be helpful to try disabling one or more lines, to see what effect this has.  You can disable any row filter in a custom query by right-clicking on it, and selecting Disable from the dropdown menu that appears.  The line will then display with greyed text, to show that it is disabled.  To re-enable it, right-click on it again, and select Enable from the dropdown menu that appears.