Default Segment

Users can specify default segment for tables using the following domain specific property:

       "OPM_PD_Segment" "segname"

where segment is a segment name.

If the OPM_PD_Segment is specified as a class property for object class , then all the (primary or auxiliary) tables generated for class are created on segment segname. If the OPM_PD_Segment is specified as an attribute for a set-valued or list-valued attribute A, then the auxiliary table for A is created on segment segname. Note that attribute OPM_PD_Segment property overrides the corresponding class OPM_PD_Segment property. Again, the OPM_PD_Segment property has no effect if it is defined in a single-valued attribute, a derived attribute, or a derived class.

The user can also specify default segment for primary version tables using the following domain specific property in a class definition:

       "OPM_PD_Segment_V" "segname"

For example, the following object class is defined with domain specific properties for physical database design:

  OBJECT CLASS PERSON
    DESCRIPTION: "person"
    PROPERTIES: "OPM_PD_Segment" "segment1",
                "OPM_PD_DefIndex" "off",
                "OPM_PD_Index.1"
                  "create nonclustered index person_indx1 on PERSON (lastName)"
    ID: ssn
    REP: firstName, lastName
    ATTRIBUTE ssn: [1,1] CHAR(9)
    ATTRIBUTE firstName: [1,1] CHAR(40)
    ATTRIBUTE lastName: [1,1] CHAR(40)
    ATTRIBUTE age: [0,1] INTEGER
    ATTRIBUTE address: set-of [0,] VARCHAR(80)