Oraclesequence的order_noorder选项

文章作者 100test 发表时间 2007:10:24 13:15:10
来源 100Test.Com百考试题网

CREATE SEQUENCE command

PURPOSE:
To create a sequence. A sequence is a database object from which
multiple users may generate unique integers. You can use sequences
to automatically generate primary key values.

SYNTAX:

CREATE SEQUENCE [schema.]sequence
[INCREMENT BY integer]
[START WITH integer]
[MAXVALUE integer | NOMAXVALUE]
[MINVALUE integer | NOMINVALUE]
[CYCLE | NOCYCLE]
[CACHE integer | NOCACHE]
[ORDER | NOORDER]

where:

schema
is the schema to contain the sequence. If you omit schema, Oracle
creates the sequence in your own schema.

sequence
is the name of the sequence to be created.

INCREMENT BY
specifies the interval between sequence numbers. This value can be
any positive or negative Oracle integer, but it cannot be 0. If
this value is negative, then the sequence descends. If the
increment is positive, then the sequence ascends. If you omit this
clause, the interval defaults to 1.

MINVALUE
specifies the sequence’s minimum value.

NOMINVALUE
specifies a minimum value of 1 for an ascending sequence or -10
for a descending sequence.

The default is NOMINVALUE.

MAXVALUE
specifies the maximum value the sequence can generate.