MariaDB starting with 10.3

CREATE SEQUENCE is being introduced in MariaDB 10.3. Details may still change before 10.3 is released as beta.

Syntax

CREATE [OR REPLACE] [TEMPORARY] SEQUENCE [IF NOT EXISTS] sequence_name [ INCREMENT [ BY | = ] increment ] [ MINVALUE [=] minvalue | NO MINVALUE | NOMINVALUE ] [ MAXVALUE [=] maxvalue | NO MAXVALUE | NOMAXVALUE ] [ START [ WITH | = ] start ] [ CACHE [=] cache | NOCACHE ] [ CYCLE | NOCYCLE] [table_options]

The options for CREATE SEQUENCE can be given in any order, optionally followed by table_options.

table_options can be any of the normal table options in CREATE TABLE but the most usable ones are ENGINE=... and COMMENT=.

NOMAXVALUE and NOMINVALUE are there to allow one to create SEQUENCE's using the Oracle syntax.

Description

CREATE SEQUENCE will create a sequence that generates new values when called with NEXT VALUE FOR sequence_name. It's an alternative to AUTO INCREMENT when one wants to have more control of how the numbers are generated. As the SEQUENCE caches values (up to CACHE) it can in some cases be much faster than AUTO INCREMENT. Another benefit is that one can access the last value generated by all used sequences, which solves one of the limitations with LAST_INSERT_ID().

DROP SEQUENCE can be used to drop a sequence,

Arguments to create

The following options may be used:

OptionDefault value Description
INCREMENT 1Increment to use for values. May be negative
MINVALUE1 if INCREMENT > 0 and -9223372036854775807 if INCREMENT < 0Minimum value for the sequence
MAXVALUE9223372036854775806 if INCREMENT > 0 and -1 if INCREMENT < 0Max value for sequence
STARTMINVALUE if INCREMENT > 0 and MAX_VALUE if INCREMENT< 0First value that the sequence will generate
CACHE1000 Number of values that should be cached. 0 if no CACHE. The underlying table will be updated first time a new sequence number is generated and each time the cache runs out.

If CYCLE is used then the sequence should start again from MINVALUE after it has run out of values. Default value is NOCYCLE.

Constraints on create arguments

To be able to create a legal sequence, the following must hold:

  • MAXVALUE >= start
  • MAXVALUE > MINVALUE
  • START >= MINVALUE
  • MAXVALUE <= 9223372036854775806 (LONGLONG_MAX-1)
  • MINVALUE >= -9223372036854775807 (LONGLONG_MIN+1)

Note that sequences can't generate the maximum/minimum 64 bit number because of the constraint of MINVALUE and MAXVALUE.

See also

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