To facilitate:

        Multi-Object/Document Transactions,

        Differentating a read with: a bad ID vs by ID of a Deleted Document from a previous query,

        Optimistic Locking,

    All Objects/Documents should support the following fields:

        Schema Version,

        Object/Row/Document Version #,

        ActiveTransaction Reference,

        Deleted flag, &

        Deleting flag.

When initiating a change/update, if the "Deleted flag" is set then an Error Dialog should be shown.
Likewise, if the "ActiveTransaction Reference" exists, then the change/update should be delayed (with a possible) dialog.

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Multi-Object/Document Transactions:

  "Commit" steps:

    1) Create a DetailedTransactionWorklist Object which contains change/rollback
       Sub-Objects for each Object in the Transaction, e.g.:

        a) Collection

        b) ID

        c) Action:

            1) Delete *1*.

            2) Insert w/ all the fields.

            3) Update (w/ sets) *1* all changed fields (grouped by Add, Delete, & Update;
               w/ Delete & Update having the original values).

            4) Adjust (w/ only numerical "adjust by" fields) all changed fields w/ "adjust by" amounts.

          *1* - These actions must also include the current Document Version # for Optimistic Lock Management.

    2) Record the DetailedTransactionWorklist to a "new" ActiveTransaction Document.
       The ActiveTransaction Document should not only contain the DetailedTransactionWorklist, but:

        a) GC-Timestamp - How far in the future? (Minutes): 2 ????????

        b) Success flag initially false / null.

    3) See "Active Transaction Rollback", If there is any failure in the following:

        a) Apply the changes from the DetailedTransactionWorklist for each Document, recording the
           success/failure into the DetailedTransactionWorklist Object.  In addition to setting the
           ActiveTransaction Reference to the ActiveTransaction ID, then based on the Action do:

            1) Delete: Set the DeletingFlag=TRUE & INC the Document Version #.

            2) Insert: Document w/ all the fields.

            3) Update: Apply the changes & INC the Document Version #.

            4) Adjust: Apply the changes & INC the Document Version #.

        b) Update the ActiveTransaction with "Success=TRUE".

        c) Update each Document in the DetailedTransactionWorklist to finish the ActiveTransaction;
           For each Action:

            1) Delete: Delete the Document by: Setting Deleted=TRUE, and clearing the rest of the Document.

            2) Insert, Update & Adjust: Clear the ActiveTransaction Reference.

    4) Delete the ActiveTransaction Document.


Active Transaction Rollback:

  Since the DetailedTransactionWorklist Object is "Up To Date" in memory, all Rollback Data & State is already
  available.

  "Active Rollback" steps:

    1) For each Successful change in the DetailedTransactionWorklist Object, do the following based on the Action:

        a) Delete: Clear the DeletingFlag!=TRUE & INC the Document Version #.

        b) Insert: Delete the Document by: Setting Deleted=TRUE, and clearing the rest of the Document.

        c) Update: Apply the "Reversing" changes & INC the Document Version #.

        d) Adjust: Apply the "Reversing" changes & INC the Document Version #.

    2) Delete the ActiveTransaction Document.


Active Transaction Garbage Collection:

  A background Thread should run every few Minutes (???? the timing) that looks for ActiveTransaction Document(s) that have their "GC-Timestamp" in the past, and process them.

  For an ActiveTransaction Document that has been marked with "Success=TRUE", then proceed w/
  ActiveTransaction "Completion":

    1) Log & Skip this ActiveTransaction Document, If there is any failure in the following:

        a) Update each Document in the DetailedTransactionWorklist to finish the ActiveTransaction;
           For each Action:

            1) Delete: Delete the Document by: Setting Deleted=TRUE, and clearing the rest of the Document.

            2) Insert, Update & Adjust: Clear the ActiveTransaction Reference.

        b) Delete the ActiveTransaction Document.

  For an ActiveTransaction Document that has NOT been marked with "Success=TRUE", then proceed w/
  ActiveTransaction "Rollback":

    1) Log & Skip this ActiveTransaction Document, If there is any failure in the following:

        a) For each change in the DetailedTransactionWorklist Object, If the Document exists AND
           the ActiveTransaction Reference refers to the current ActiveTransaction Document, then
           do the following based on the Action:

            1) Delete: If the DeletingFlag==TRUE, then clear it & the ActiveTransaction Reference, and
               INC the Document Version #.

            2) Insert: Delete the Document by: Setting Deleted=TRUE, and clearing the rest of the Document.

            3) Update: Apply the "Reversing" changes & INC the Document Version #.

            4) Adjust: Apply the "Reversing" changes & INC the Document Version #.

        b) Delete the ActiveTransaction Document.