31 lines
1.4 KiB
Plaintext
31 lines
1.4 KiB
Plaintext
ID: availbl promise debt
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Club: 0 +7200 -23450
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john: 7200 +0 -7200
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# Reflect john paying its bills all at once ...
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Club: 7200 +0 -23450
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john: 0 +0 0
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# Charge Club with server hosting provided by alex ...
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Club: 0 +0 -16250
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alex: 7200 +16250 0
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# Some updates and deletes that could, unless denied, destroy consistency ...
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Error: near line 42: paid is set and adjusted automatically according to added Transfer records
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Error: near line 43: Debt is involved in transfers to revoke at first
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Error: near line 44: FOREIGN KEY constraint failed
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# After revoking transactions, you are free to change or delete debts and credits ...
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Club: 7200 +0 0
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alex: 0 +0 0
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# But let's rollback that what-if excurse. This is how it currently is ...
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Club: 0 +0 -16250
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alex: 7200 +16250 0
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###################################################################
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# Now it is your turn: Study the sql code yielding the output above
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# then enter new members and let them pay the fees.
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# (PLUS: Let have one discalculia and pay too little or too much.)
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# Once the club has enough money to pay alex' hosting service,
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# update (i.e. revoke and reenter) the respective transaction.
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# Finally issue a bank transfer to alex. Hint: An outgoing transfer
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# is simply a debt charging alex' own virtual account and without
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# targetCredit (NULL). PLUS: What happens if the description of
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# the bank transfer does not contain any or only a wrong IBAN?
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