Database Technology Department
Palo Alto, California
SQL3 Discussion Paper
ANSI Number: X3H2-93-494
Nov. 15, 1993
Title: Semantics of the INSTANCE Keyword (Possible Problem)
Author: William Kent
1 X3H2-93-359R/ISO DBL MUN-003, (ISO-ANSI Working Draft) Database Language SQL (SQL3), Jim Melton (ed.), August 1993.
2 X3H2-93-384R, "Extents for object ADTs", Sept 10 1993, by John Bellemore, Tim Nguyen, Gray Clossman and Phil Shaw.
The INSTANCE keyword introduced with the adoption of  has some subtle semantic implications which, if unintended, constitute a possible problem. If they are intended, it would be useful to clarify the point.
Add the following material as a new possible problem in .
The INSTANCE keyword introduced with the adoption of  has some subtle semantic implications which may not have been intended. These are illustrated using the example
CREATE TABLE EMP
SPOUSE PERSON INSTANCE,
[Editorial note. Was that last point made clear in the adopted changes? If not, then that also needs clarification in the standard.]