PDMS.DRAFT.User.Guide.Part1

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If a Draft (PADD) DB has been created as a multiwrite database, several users can
write to it simultaneously, although they cannot change the same element.
Multiwrite databases can either be Standard multiwrite databases, or Extract
databases. In both types, an element must be claimed before it can be modified.
Claiming an element prevents other users claiming (and modifying) the element; the
element must be unclaimed or released before another user can change it.
Claiming can be either explicit, where the user must use the CLAIM command before
attempting to modify the element, or implicit, where the claim is made automatically
when the user tries to modify the element. The claim mode is set when the DB is
created. For full details see the VANTAGE PDMS ADMIN Command Reference Manual
where DBAC is a pseudo-attribute, which can have the text settings CONTROL,
UPDATE or MULTIWRITE.