| Things
To Do (page 95) |
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1(a)
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 |
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(b)
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It
needs to be in the same order as the master file otherwise there
would be too much forward and backward winding of the tape which
would take a long time. |
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(c)
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Their
Account Number or Customer Number |
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(d)
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The primary key field |
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(e)
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The master file has not been updated by the transaction file.
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(f)
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The
bottom left tape file on the diagram (i.e. the updated customer
file) |
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(g)
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The old customer file |
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(h)
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After
the validation and update stages. |
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(i)
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The old customer file, the new customer file and the payments
transaction file. |
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2(a)
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So
that the transactions are in the same order as the master file.
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(b)
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Amendment
Insertion Deletion |
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(c)
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Reference
to a record which is not included in the master file. An instruction
to delete a record which was deleted during the last update.
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