View #
A view is from metadata perspective a hybrid between a table and a mapping. It contains columns (without data type definition) and their mappings in a single element.
It looks like a view on the picture:
Overview #
The Overview card contains all attributes described in Overview card description in the common area of this documentation.
There are no specific attributes.
Columns #
| Attribute | Description |
|---|---|
| Name | The column name. The name should be descriptive to serve for quick orientation in metadata. |
| Code | Code is a shortened name of the column - See Code generation principles |
| Description | A free text explaining the column meaning |
| Comment | A free text commenting the column |
| Mapping | A SQL statement that fills the column |
Sources #
Similarly to mappings, even views are based on SQL command. Sources tab contains data from FROM clause, ideally in structured form to keep the links to the sources (it is possible to write the whole FROM clause to the TEXT tab, but it is better to break it to a separate parts).
Each source has a stereotype - it specify how the source is joined. Options are
- FROM
- JOIN
- LEFT JOIN
- RIGHT JOIN
- FULL OUTER JOIN
It is possible to use several kinds of sources:
- TABLE
- VIEW
- SUBSELECT
- DUMMY
The rest of the attributes is known from SQL:
| Attribute | Description |
|---|---|
| Source object | Source object is selected from the list of objects of selected type |
| Owner | Owner of the selected object, one of System users |
| Source subselect | Only for SUBSELECT stereotype. It allows to enter subselect. |
| Alias | A shortened identification of the source |
| Expression | How the source is connected to the rest sources (ON condition) |
| Source Context | Other text metadata that can be used in the template for specific purposes |
| Sources description | A free text that allows to comment sources if necessary |
| Criteria | WHERE clause from the SQL |
| Criteria description | Description of the criteria |
For generation of output scripts, it is necessary to create a template.