This panel enables you to define parameters of the CREATE TABLE command for the Entity or Relationship. Further definitions are available for the components of the Entity or Relationship.
All the options that are written in capital letters refer to keywords of the CREATE TABLE command. For full details please see your SQL language reference manual.
Transformation Rule
Generate Table for Supertype: This option is only relevant for total generalizations. The set of the subtypes of a total generalization completely describes the information depicted by the supertype. Therefore normally no separate table is generated for the supertype. If this option is switched on then a separate table is generated for the supertype Entity. If the supertype has another Relationship then a separate table is always generated for the supertype.
Amalgamate: This option is only available for Relationships and is ignored if the Relationship has key or non-key attributes, or for 1:n Relationships.If this option is not switched on or if the Relationship is defined then a separate table is generated for the Relationship. Otherwise the key attribute of the 'one' Entity is added as a foreign key to the 'many' Entity. This action is called combining or "amalgamating".
User Name. The user name given here is prefixed to the table name. This overrides the "Table owner" option given when starting Data Base Designer.
TABLESPACE specifies the tablespace in which the table will be created.
STORAGE specifies the storage characteristics for the table. This field can contain any text, including "(" and ")", that is allowed in the Oracle STORAGE Clause.
CLUSTER specifies the cluster of which the table is to be a part. The columns listed in this clause are the table columns that correspoond to the cluster's columns.Data Base Designer simply transfers this information to the CREATE TABLE command without checking. You should include your own user statement if necessary.
PCTFREE specifies the percentage of space in each of the table's data blocks reserved for future upgrades to the table's rows.
PCTUSED specifies the minimum percentage of used space that is maintained for each data block of the table.
INITRANS specifies the number of initial transaction entries allocated within each data block allocated to the table.
MAXTRANS specifies the maximum number of concurrent transactions that can update a data block allocated to the table.
CHECK explicitly defines a condition. The CHECK constraint is added to CREATE TABLE command after the primary key statement.
AS inserts the rows returned by the sub-query into the table upon its creation.
CONSTRAINT defines an integrity constraint. An integrity constraint is a rule that restricts the values for one or more columns in a table.Remember that all the constraints that are inherent to the Information Model, such as primary keys and referential constraints for the foreign key are automatically generated by Data Base Designer. Use this field to define any additional constraints that may be needed.
Epilog. This field can contain any other keywords and parameters that you need to complete the CREATE TABLE command. The text is inserted into the CREATE TABLE command in front of the terminating ";".