Return to RelationshipKeySetter.h CVS log

Up to [NeXTSTEP 3.3 examples] / Examples / EnterpriseObjects / MasteringDetails / EOFExtensions.subproj

Sample Programs from NeXSTEP 3.3

/* RelationshipKeySetter.h created by cfeder on Tue 08-Nov-1994 */

#import <eoaccess/eoaccess.h>

@interface EOEntity (attrsNamed)
- attributesNamed:(NSArray *)names;
- createObject;
@end

// Extensions to EORelationship to handle assigning foreign keys in
// objects when they are newly assigned to point at one another.
// For instance, if an employee is set to point at a new department object
// [toEmpRelationship updateKeysForSourceObject:theEmp destinationObject:theNewDept]
// will change to dept_id property of theEmp to the dept_id of theNewDept
// and return the modified object (theEmp) so the caller can make sure that object
// is updated in the database.
//
// The following relationship types are handled:
//
// M     Detail   Insert rule              Delete                 Types
// PK -> PK       D->PK := M->PK           delete D               to-one
// FK -> PK       M->FK := D->PK           M->FK=NULL             to-one
// PK -> FK       D->FK := M->PK           Delete D               to-many
// Many to many   create link obj          Delete link            to-many
//
// Decoding: The first line means, when a relationship joins from the
// primary key of the master entity to the primary key of the detail,
// handle and insertion by setting the primary key of the detail to match
// the primary key of the master.
//
@interface EORelationship (setPropsInDestObject)
- (NSArray *)sourceKeys;
- (NSDictionary *)destinationValuesFromSourceObject:sourceObject;
- (void)setJoinPropertiesInDestinationObject:destination fromSourceObject:source;
- (void)setJoinPropertiesInSourceObject:source fromDestinationObject:destination;
- (BOOL)hasJoinsOnPrimaryKeyOfSourceEntity;
- (void)updateMasterObject:master withNewDestinationObject:destination;
- linkObjectForSourceObject:master destinationObject:destination;
- updateKeysForSourceObject:source destinationObject:destination;
    // Sets keys on source or destination to maintain consistency for
    // the source to now map to destination for this relationship.
    // Does not actually assign destination to ivar in source (just messes
    // with the keys).
    // Returns the modified object (source or destination). In the case of
    // a many to many returns a newly created link object.

- updateKeysForDeleteOfDestinationObject:destination fromSourceObject:source;
    // Sets keys on source or destination to maintain consistency for
    // a delete of the destination from the source.  Returns the object
    // modified, or a synthesized link object that must be deleted to
    // affect the delete.  The caller is responsible for updating the
    // source object, or deleting the destination or link in the database.
    //
    // This does not actually update destination to ivar in source (just messes
    // with the keys).
@end

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.