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Specifying the sql:inverse Attribute on sql:relationship (SQLXML 4.0)

The sql:inverse attribute is useful only when the XSD schema is used for either bulk load or by an updategram. The sql:inverse attribute can be specified on the <sql:relationship> element. In updategrams, the updategram logic interprets the schema in determining the tables and columns that are updated by the updategram operation. The parent-child relationships that are specified in the schema determine the order in which the records are modified (inserted or deleted).

If you have an XSD schema in which the parent-child relationship is specified in the inverse order of the primary-key/foreign-key relationship between the corresponding database columns, the insert or delete updategram operation will fail because of the primary-key/foreign-key violation. In such cases, the sql:inverse attribute is specified (sql:inverse="true") in the <sql:relationship> element, and the updategram logic inverses its interpretation of the parent-child relationship specified in the schema.

The sql:inverse attribute takes a Boolean value (0=false, 1=true). The acceptable values are 0, 1, true, and false.

For a working sample using the sql:inverse annotation, see Specifying an Annotated Mapping Schema in an Updategram.