Database Management
Reference Manual
Multiwrite Databases Claims and Extracts
:
User Claims
: Notes on Standard Multiwrite DBs
Notes on Standard Multiwrite DBs
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Elements cannot be claimed if recent changes have been made to them by other users. You must issue a GETWORK command first.
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Elements cannot be unclaimed if there are updates outstanding. You must issue a SAVEWORK command first.
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You can insert/remove primary elements in a members list without claiming the owner. For example, you can add a Branch to a Pipe without claiming the Pipe. Thus two users can add different Branches to the same Pipe: any discrepancies will be resolved when a SAVEWORK is attempted.
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Before an element can be deleted, that element and all of its sub-hierarchy must be claimed.
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The following potential problems may not be revealed until you try to save changes:
1.
If two concurrent users allocate the same name to different elements, the second user to attempt a SAVEWORK will show up an error. The second user must rename their element.
2.
If one user inserts a significant element into another element’s list, while a concurrent user deletes the latter element, an attempt to SAVEWORK will show up an error. Either the first user must delete or move the significant element, or the second user must QUIT without saving the deletion.
1974 to current year.
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