SQL - CREATE SEQUENCE
Creates a new sequence. Command introduced in version 2.2.
Syntax
CREATE SEQUENCE <sequence> TYPE <CACHED|ORDERED> [START <start>]
[INCREMENT <increment>] [CACHE <cache>]
<sequence>
Logical name for the sequence to cache.TYPE
Defines the sequence type. Supported types are,CACHED
For sequences where it caches N items on each node to improve performance when you require many calls to the.next()
method. (Bear in mind, this may create holes with numeration).ORDERED
For sequences where it draws on a new value with each call to the.next()
method.
START
Defines the initial value of the sequence.INCREMENT
Defines the increment for each call of the.next()
method.CACHE
Defines the number of value to pre-cache, in the event that you use the cached sequence type.CYCLE
Defines if sequence will restart fromSTART
value afterLIMIT
value reached. Default value isFALSE
.LIMIT
Defines limit value sequence can reach. After limit value is reached cyclic sequences will restart from START value, while non cyclic sequences will throw message that limit is reached.ASC | DESC
Defines order of the sequence.ASC
defines that next sequence value will becurrentValue + incrementValue
, whileDESC
defines that next sequence value will becurrentValue - incrementValue
(assuming that limit is not reached). Default value isASC
.
Examples
-
Create a new sequence to handle id numbers:
orientdb>
CREATE SEQUENCE idseq TYPE ORDERED
-
Use the new sequence to insert id values
orientdb>
INSERT INTO Account SET id = sequence('idseq').next()
For more information, see