Queries
The Queries tab initially contains the following controls:
- Group 1
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The default query group. All queries must belong to a query group.
- +Add query
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Click to create a query in Group1. You can add any number of queries to the Data Source in order to retrieve the content items you require. You can either add them all in the same group, or in different groups if necessary. In many cases a single query is sufficient. Adding more than two or three queries in total is likely to carry a performance penalty.
The following dialog is displayed:
Either select the type of query you want to add or click on to close the dialog. Selecting a query type adds a form to the group.
- Apply filter & sort
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Determines whether or not the filters and sorting rules defined on the Filter & sort tab are to be applied to the queries in this group. If this option is switched on, then the results returned by all the queries in the group are merged to a single set, and the filters and sorting rules are applied to this merged set. Otherwise, the individual query result sets are returned in the order of the queries within the group.
- +Add query group
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Click to create a new query group.
- Maximum items
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The maximum number of items to be returned by this query. Once all filtering and sorting has been carried out, only the specified number of items from the top of the resulting sequence are returned.
The query forms are collapsible. If the tab contains several queries like this:
you can just click on the title bar of a query to expand it. Any other open query form will be collapsed.
There are seven different query types, described in the following sections.