NULL
| Database | Default | "NULL" allowed in Definition | Notes |
|---|---|---|---|
| Access 2000 | NULL | yes | |
| DB2 8.1 | NULL | no | |
| Firebird 1.5 | NULL | no | |
| FrontBase 4.1 | NULL | no | |
| MySQL 4.0 – 4.1 | NULL | yes | |
| Oracle 9.2 | NULL | yes | Empty strings considered NULL |
| PostgreSQL 7.4 | NULL | yes | |
| SQL Server 2000 | NOT NULL | yes | |
| SQLite 2.8 | NULL | yes | |
| Sybase ASE 12.5 | NOT NULL | yes |
Output formatting handled by PEAR::DB's DB_PORTABILITY_NULL_TO_EMPTY configuration option.
- Default
-
The default nullability state when a NOT NULL constraint is not used
eg: CREATE TABLE t (i INT) - "NULL" allowed in Definition
-
Can the column be defined as being nullable by using "NULL"
eg: CREATE TABLE t (i INT NULL)