[DERBY-2167] Slightly misleading error message for UNIQUE constraint without NOT NULL constraint

• Type: Bug
• Status: Closed
• Priority: Trivial
• Resolution: Won't Fix
• Component/s: Miscellaneous
• Assignee: Thomas Nielsen
• Reporter: Bernt Johnsen
• Created: 12/Dec/06 10:04
• Updated: 29/Jun/09 13:13
• Resolved: 09/Nov/07 09:08

Description

With UNIQUE contraint, you get an error message which indicates you also need explicit NOT NULL constraint for PRIMARY KEY constraint, which is not true . NOT NULL is implicit for PRIMARY KEY (or more precise according to the lingo in the SQL standard: PRIMARY KEY is an alternative syntax for UNIQUE NOT NULL)

ij> create table t1 (i integer unique);
ERROR 42831: 'I' cannot be a column of a primary key or unique key because it can contain null values.
ij> create table t2 (i integer unique not null);
0 rows inserted/updated/deleted
ij> create table t3 (i integer primary key);
0 rows inserted/updated/deleted
ij> create table t4 (i integer primary key not null);
0 rows inserted/updated/deleted