I founded a solution here.
It's summarized below.
Basicaly, there is this table in the ServiceManager database called the AutoIncrementAvailableRange
table. This value stores the next available number for a particular class property.
First you need to know which row represents the property you want to update. If you just run this:
select
MT.TypeName,
MT.ManagedTypeId,
MTP.ManagedTypePropertyName,
MTP.ManagedTypePropertyID,
AIAR.FirstAvailableValue
from ManagedType as MT,
ManagedTypeProperty as MTP,
AutoIncrementAvailableRange as AIAR
where MT.ManagedTypeId = AIAR.ManagedTypeId
and MTP.ManagedTypePropertyId = AIAR.ManagedTypePropertyId

So – now let’s say we want to adjust the WorkItem ID to start at 10000. We would just run a query like this:
update AutoIncrementAvailableRange
set FirstAvailableValue = 10000
where ManagedTypeId = 'F59821E2-0364-ED2C-19E3-752EFBB1ECE9'
and ManagedTypePropertyId = '28B1C58F-AEFA-A449-7496-4805186BD94F'
It seens to work.
