Sequences

Sequences

Sequences are an SQL 2012 feature that allows you to define an automatically incrementing number. Once a number is issued, SQL automatically increments to the next number in the sequence.

ACMA provides the ability to define these sequences directly in the editor

Settings

| Name | The name of the sequence, which is used in value declarations |

Start value	The number to start the sequence from
Increment by	The number to increment by each time the sequence is called
Min value	The minimum value that can be issued
Max value	The maximum value that can be issued
Cycle	Indicates if the sequence should start again from the minimum value whenever the maximum value is reached

Using sequences

Sequences are used in value declarations using the %sequenceName% notation.

Examples

Sequences can be used to assign things like unix UID numbers, perhaps starting at 20,000 and incrementing for each assigned value.

Cycled sequences can be used to stripe users across a set of home folder groups. By setting a minimum value of 1 and a maximum of 5, each user would be assigned a value of 1-5. The sequence returns back to the start after issuing the 5th value.

Sequence names must be unique, and cannot be the same name as any of the built-in variables or constants.