For example, Figure 3-1 shows a simple selection returning all rows from the Customer table in the BIRT Analytics Demo database.A change resolution element cannot hold the top-level position in a selection. A change resolution element holding the last position in a selection causes the selection to return all records from the new table linked to all previous conditions. For example, the selection defined in the example shown in Figure 3-2 returns 868 records for households in which customers who are women directors live.For a contrasting example, add a change resolution element for each query element. This approach changes the perspective of each query in the selection. The selection in the example shown in Figure 3-3 returns all houses where customers who are female live, intersected with all houses where customers who are directors live; a total of 1009 records.An example showing a selection created in this way appears in Figure 3-4. The selection returns all houses, intersected with houses where female customers live, intersected with houses where director customers live.
Figure 3-4 Placing an All element last in a selection affects the selection by changing the resolution level to the table defined in the All element. In this case, the selection returns all female customers, intersected with director customers, intersected with all customers that have a house. In other words, this selection returns all female customers who are directors and have a house. In the BIRT Analytics Demo database, 868 records match this criteria. An example showing a selection created in this way appears in Figure 3-5.
Figure 3-5
|
|
Copyright Actuate Corporation 2013 | BIRT Analytics 4.2 |