Vertical partitioning consists in segmenting a table into multiple tables each containing a subset of columns and the same number of rows as the partitioned table. The partition tables share the same primary key.
Procedure
- Select , or right-click a table in the diagram and select to open the Vertical Partitioning Wizard.
- Select the table to partition, specify whether you want to keep the original
table after partitioning, and then click Next.
- Create as many partition tables as necessary using the
Insert and Add a Row tools
(specifying an appropriate name for each, which must be unique in the model),
and then click Next.
- Drag columns from under the original table in the
Available columns pane, to the appropriate partition
table in the Columns distribution pane, (or select source
and target tables and use the Add and
Remove buttons), and then click
Next.
- Specify a name and code for the transformation object that will be created to
preserve information about the partitioning, and then click
Finish to create a table for each partition, taking
the name of the partition. All references to the original table are created on
each partition table.
In this example, the table Customer, is divided into two
tables, each of which details one type of information about the
customer:
Before |
After |
|
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Note Vertical partitionings created in a PDM generated from another model are
preserved when applying changes from the original model. The columns absent
from each partition table in the target PDM are shown but not selected in
the Merge dialog (see Core Features Guide > Modeling with PowerDesigner > Comparing and Merging Models). Any changes in the source model are proposed, where appropriate, to
each of the partition tables, and you should deselect the change for those
partitions to which you do not want to apply it.