Primary key length.
For int type (32-bit): NUMBER(9). For long type (64-bit): NUMBER(18).
Oracle allow up to 38 significant digits in NUMBER and up to 28 digits in SEQUENCE.
- http://docs.oracle.com/cd/B28359_01/server.111/b28318/datatype.htm
- Oracle Data Types
- http://docs.oracle.com/cd/B28359_01/server.111/b28286/statements_6015.htm
- CREATE SEQUENCE.
- http://docs.oracle.com/cd/E19501-01/819-3659/gcmaz/index.html
- Java Type to SQL Type Mappings.