Page Comparison

This control provides querying for relational databases. When this control is selected, there appears a menu appears on the right side of it with the Query designer. When selecting the Data tab, under the Data Sources, there is an "Add New" button. One of the options is Database Query. 

Query

Parameters

Target schema, table, and to include all fields option is are presented at in this section.

Target Schema
Select one of the newly created or imported database schemas from this dropdown menu.

Target Table
After selecting the target schema, select a newly created or imported database table from the dropdown menu.

Include All Fields?

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Select the fields you want to include in the query result. You can specify field order using the arrow buttons on the right side.

Field
Lists columns of selected database and its related tables.

Caption
Caption The caption to display be displayed to the user. If not specified, the field is hidden to from the user.

Formula
The formula to use for aggregate values.

Mapped XPath
XPath to map field value on the data model. If not specified, Name property is used.

Order

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Value
The criteria value. You should use an expression between these double brackets {{expression}}. Expression The expression should be an XPath, for example {{Search/Identity}}.

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Ignore Values
Enter value(s) to ignore in the select query.

Blocks

In order to isolate conditions properly, you may use a block structure for the where clause. Add as many block blocks as you want and select their condition.

Sub Queries

Creates a sub-query in your select query.

Relation
Lists relations of the specified table from the main query.

Mapped XPath
XPath to map field value on the data model. If not specified, the Name property is used.

Include All Fields
Check this option if you want to include all fields in the query result.

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Options to map and format the result data.

Item XPath
XPath of the item that will be listed in the related control. If it is left empty, which is the same with as the * value, all resulting items are being listed.

List Item Formatting

Customizes the format of the control's display options.

Display Text Format
Specify the format to display the result text. You can use column names inside curly braces. Ex: {{Name}} - {{Id}}

Value Format
Specify the format of the value. You can use column names inside curly braces. Ex:  {{Id}} - {{Type}}

Selection Mappings

In order to map a column of data from the query result into an XPath, create a mapping by pressing Add New button.

Source  
Name of the data column to be mapped.

Target
XPath to map data. (Be sure to include the item xpath also. e.g. Activities/Activity) 

Hierarchy Column