You can view and modify the data module, table, column, and folder properties in the modeling interface.
The properties can be accessed from the data module, table, column, or folder context menu , or by using the Properties icon in the application bar.
Some properties, such as Label and Identifier, are available for all objects in the data module, while other properties are available only for certain types of objects. For example, Member display list is available only for data modules, Item list only for tables, and Aggregate only for columns.
You can view and modify the following properties on the General tab of the Properties pane.
Specifies the item's name that is displayed in the user interface. This property applies to all items. You can't change the label for members. To change the label for a data module, save the module by using the Save as option.
- Hide from users
Use this property to hide items, such as tables, columns, packages, or folders, in a data module. The hidden items are grayed out in the modeling interface, and not visible in other interfaces, such as reporting or dashboarding. For more information, see Hiding items.
Shows the underlying expression for a column. Click View or edit to open the expression editor where you can modify the expression.
This property applies to columns, and specifies the intended use for the column data.
The initial property value is based on the type of data that the column represents in the source. You need to verify that the property is set correctly. For example, if you import a numeric column that participates in a relationship, the Usage property is set to Identifier. You can change this property.
The following Usage types are supported:
- Represents a column that is used to group or summarize data in a Measure column with which it has a relationship. It can also represent an index, date, or time column type. For example, Invoice number, or Invoice date.
- Represents a column that contains numeric data that can be grouped or summarized, such as Product Cost.
- Represents a column that is not an Identifier or a Measure, such as Description.
This property applies to columns, and defines the type of aggregation that is applied to a summary column in a report or dashboard. For example, if the Aggregate property value of the Quantity column is Total, and the column is grouped by Product Name in a report, the Quantity column in the report shows the total quantity of each product. Aggregated data improves query performance and helps to retrieve data faster.
The default type of aggregation is inherited from the source. When modifying this property, you can select values that the source does not provide, such as average or maximum. To know which aggregate value is required, you must understand what your data represents. For example, if you aggregate Part number, the aggregate values that apply are count, count distinct, maximum, and minimum.
The following aggregation types are supported:
- None (no aggregation is set up for a column)
- Count distinct
- Data type
The column data type is inherited from the source and can't be modified in the data module.
Use this property to specify whether a column includes the date or time, or geographic location type of data. This information is used in the reporting and dashboarding environments to suggest the most appropriate default visualizations, among other possibilities.
- Geographic location
- The values include Continent, Sub Continent, Country, Region, State Province, County, City, Postal code, Street Address, Position, Latitude, and Longitude.
- The values include Date, Year, Quarter, Season, Month, Week, Day, Hour, Minute, and Second.
- Lookup reference
This column property is used to create a data module for relative date analysis. For more information, see Creating a data module for relative date analysis.
Use this column property to enable or disable displaying relational members in the data tree. The following settings are available:
- Members can be expanded in the data tree. Sorting is enabled, and members are sorted by the current column. Sort order is Ascending. This is the default setting.
- Members can be expanded in the data tree. You can select the column to sort by, and set the sort order to Ascending or Descending. The members that are shown in the data tree don't dynamically adjust to the changed sort order. Use the Refresh members action from the column context menu for the sort order to be reflected in the data tree.
- Members can't be expanded in the data tree. Previously shown members are removed, and new members can't be loaded for the column.
For more information, see Displaying relational members.
- Members display limit
This data module property is used to specify the maximum number of members to load in the data tree nodes for each fetch request. For more information, see Setting the members display limits.
Use this property to specify optional information about the data module, table, column, or folder. The description is available in reports and dashboards that are based on the data module.
Use this property to specify optional information about the data module, table, column, or folder. Applies to all items in the data module. The comment is available only within the data module environment.
- Screen tip
Use this property to specify an optional short description of the table or column. Applies to all items in the data module. The screen tip appears when you pause your pointer over the table or column name in the modeling, reporting, or dashboards environment.
The following properties are specified on the General tab, Advanced section, of the Properties pane:
This property uniquely identifies objects. It is used, either by itself or in conjunction with parent object identifiers, to generate SQL queries, in expressions, reports, dashboards, and other objects. The property is created automatically for a data module and all its objects. For tables and columns, the Identifier property value is inherited from the data source. The property can be modified for all objects except for folders and the data module itself. To change the data module identifier, save the data module under a different name.When changing this property, ensure that its value meets the following conditions:
- The first character is a letter or an underscore (_).
- The subsequent characters are letters, digits, or underscores (_), without spaces.
- Technical data type
This property reflects how the column is defined in the database. For example, for a column with the Data type of
Text, the Technical data type might be
This property applies to tables. It controls how the query engine should understand and process the table, and its child objects, in a query. The Usage property has the following settings:
- This setting informs the query engine that the table is an ordinary table, and requires no special processing. This is the default setting.
- The bridge table is used to remove the many-to-many relationships between tables by setting the many side of the relationship to the bridge table. By default, the Cognos Analytics query engine understands tables that are at the many end of relationships to be fact tables. The bridge table is not a fact table. So for the query engine to understand the role of the table and properly generate the query, the bridge table Usage property must be set to Bridge.
- The bridge table can be defined either in the database or in the data module (or Framework Manager model). However, it is preferable to create bridge tables in the database.
- This setting summarizes the values in the table. When the table is used in a report or dashboard, the data retrieved from the table is already summarized, columns with the Usage property set to Measure are aggregated, and all other columns are used as grouping columns.
Summary tables, such as unions, joined views, excepts, intersects, and SQL-based tables can be modeled in reports and data modules. It is more efficient to model these tables in the data module because they can be available for all reports and dashboards. The tables are modeled once, there is only one possible point of failure, and the generated numbers are consistent.
- Item list
Use this property to specify the SQL generation type for a table. Depending on the setting for this property, the generated query SQL includes all or only selected columns. This property applies to tables only. For more information, see Generating the query SQL.
- Data cache
Use this property to enable data caching and specify the cache expiry options for tables in the data module. For more information, see Setting up data caching.
This property applies to all objects in the data module. For a table or column, it shows the source name and path.
- Supports NULL values
Specifies whether a column supports null values. By default, this property value is inherited from the source. You can change this value.