partitionable
Type: Boolean
The read-only partitionable property of the DbFile class specifies whether partitioning rules are to be enforced for the DbFile instance. This property can be set if at most one class is mapped to the file.
You may want to allow instances of a class (for example, the Sale class, which is mapped to sale.dat) to be partitioned when the system is deployed. (The decision is to be left to the administrator of the deployed system.) To prevent another class being mapped inadvertently to sale.dat if it has not been physically partitioned in the development environment, set the partitionable property to true.
When the partitionable property is set to true, the compiler and the JADE development environment enforce file partitioning rules for the schema-defined DbFile instance irrespective of whether the file is physically partitioned.
Setting the partitionable property to false does not prevent a file from being partitioned. To enable partitioning on an empty database file, execute the setPartitioned method of the DbFile class passing true as the parameter. When partitioning is enabled on a database file, the partitionable property is also set if it was not already set.
You can change the value of the partitionable property:
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From the JADE development environment, by checking the Partitionable check box on the File dialog. This check box is disabled if it is not valid for the selected file. If you check the check box for a new file, JADE ensures that the file is not used elsewhere.
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During a batch schema load.
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By calling the DbFile class setPartitioned method.
When the value of the partitionable property is set to true, there can be one partitionable file only with a specific name and number in the database, and collections cannot be mapped to the file.
