Eclipse BIRT Report Object Model (ROM)
DataSet Element
Display Name: | Data Set |
Since: | 2.1 |
XML Element: | None |
Extends: | ReportElement |
Extendable: | No |
Abstract: | Yes |
Name Space: | Data Sets |
Name Requirement: | Required |
Allows User Properties: | Yes |
Has Style: | No |
comments, customXml, displayName, displayNameID, eventHandlerClass, extends, name, newHandlerOnEachEvent, propertyMasks, userProperties, viewAction
Cached derived data attributes of a data set.
Type: | CachedMetaData Structure |
Since: | 1.0 |
Required: | No |
Display Name: | Cached metadata |
JavaScript Type: | |
Default Value: | None |
Inherited: | Yes |
Runtime Settable: | Yes |
Property Sheet Visibility: | Hidden |
Property Sheet Group: | Top |
Defines the cached derived data attributes of a data set. The BIRT designer uses the cached information until the user initiates refresh and reconciles with the latest derived data attributes provided by the connected data source. This property is used during report design time only; its content is maintained by the BIRT designer tool.
CachedMetaData structure
Defines the report-related data attributes of the result set�s columns.
Type: | List of ColumnHint Structures |
Since: | 1.0 |
Required: | No |
Display Name: | Column hints |
JavaScript Type: | |
Default Value: | None |
Inherited: | Yes |
Runtime Settable: | Yes |
Property Sheet Visibility: | Hidden |
Property Sheet Group: | Top |
In BIRT, a result set column can be defined with an alias. Aliases are useful in cases where a column name is awkward, or is used by multiple columns in a result set.
BIRT reports provide a rich viewing experience. The user can search the report, extract data to a file, export data to an OLAP system, and more. Such operations work on the actual data set�s result set instead of on the presentation of the data. Column hints let the report developer customize the search and data extract experience.
The column hint element provides a number of "hints" about result set columns. The hints override BIRT defaults for how columns are handled during viewing. Hints can be provided for both retrieved and computed columns.
Column hints are keyed to the data set�s primary result set using names. The user must understand how to keep the hints in sync with the data set when either the data set definition, or underlying data source, changes.
BIRT uses the column hints in the following cases:
In each case, BIRT checks whether the data set provides the requested column. If so, it continues processing the report. If not, it issues a fatal runtime error.
ColumnHint structure
User-defined columns in the result set.
Type: | List of ComputedColumn Structures |
Since: | 1.0 |
Required: | No |
Display Name: | Computed columns |
JavaScript Type: | |
Default Value: | None |
Inherited: | Yes |
Runtime Settable: | Yes |
Property Sheet Visibility: | Hidden |
Property Sheet Group: | Top |
A computed column is a user-defined column produced as an expression of other columns within the data set�s primary result set. It is not of the columns retrieved directly from the underlying data provider.
An optional set of filters to apply to the result set before any other data transforms.
Type: | List of FilterCondition Structures |
Since: | 1.0 |
Required: | No |
Display Name: | Filter |
JavaScript Type: | |
Default Value: | None |
Inherited: | Yes |
Runtime Settable: | No |
Property Sheet Visibility: | Hidden |
Property Sheet Group: | Top |
An optional set of filters that apply to the data set�s primary result set. A data set�s filter is applied to each row of the retrieved result set before any other data transforms. The filter expression should thus not contain any aggregation functions. It usually references at least one column from a data row, and may also reference a report parameter or other scripting variable.
Filter Criteria structure
Listing filter
property
ListingGroup filter
property
Type: | boolean |
Since: | 2.3 |
Required: | No |
Display Name: | Needs cache for data-engine |
JavaScript Type: | |
Default Value: | false |
Inherited: | Yes |
Runtime Settable: | No |
Property Sheet Visibility: | Visible |
Property Sheet Group: | Top |
Defines the data access attributes of the list of input and/or output parameters.
Type: | List of DataSetParam Structures |
Since: | 1.0 |
Required: | No |
Display Name: | Data set parameters |
JavaScript Type: | |
Default Value: | None |
Inherited: | Yes |
Runtime Settable: | Yes |
Property Sheet Visibility: | Hidden |
Property Sheet Group: | Top |
Many data sets allow parameters, which can be of input and/or output modes. For some, the user must define the parameters as part of the data set definition. For other data sets, the driver itself can provide the set of parameter definitions from the information available in a data set query. In the latter case, parameter definitions are derived data and are not stored in the parameter definition.
Some drivers refer to a parameter by position. Others can refer to a parameter by name. Also, for some data sets, the data set definition can omit parameter definitions for optional parameters not used within the report. Not all parameter properties are required. If a property is omitted. BIRT assumes that the data set implementation can provide it at run time. If the driver cannot provide the information, then a runtime error occurs. This is an optional list of data set parameter definitions, used only when the underlying data provider cannot provide this information. When contradicting meta-data are found between those provided dynamically by a data provider and those specified in a data set definition, the data provider�s meta-data takes precedence.
ComputedColumn structure
Type: | List of ResultSetColumn Structures |
Since: | 2.1 |
Required: | No |
Display Name: | Result set hints |
JavaScript Type: | |
Default Value: | None |
Inherited: | Yes |
Runtime Settable: | Yes |
Property Sheet Visibility: | Hidden |
Property Sheet Group: | Top |
Type: | integer |
Since: | 2.2 |
Required: | No |
Display Name: | Max number of rows to fetch from data set |
JavaScript Type: | |
Default Value: | None |
Inherited: | Yes |
Runtime Settable: | Yes |
Property Sheet Visibility: | Visible |
Property Sheet Group: | Top |
List of sort hints which support row ordering.
Type: | List of SortHint Structures |
Since: | 2.5 |
Required: | No |
Display Name: | Sort hints |
JavaScript Type: | |
Default Value: | None |
Inherited: | Yes |
Runtime Settable: | Yes |
Property Sheet Visibility: | Hidden |
Property Sheet Group: | Top |
List of sort hints which support row ordering.Sort hint can be mapped to ODA corresponding values.
SortHint structure