So, about 6 weeks of PL/1 training, coding some pretty big programs (what they actually were/did, I don't remember) and I am ready for some work. The system I start on is for Mortgage administration; the company loaned money to both individuals and businesses, although the individual business was wound down by the mid-80's. This also meant staff mortgages as a benefit, which I and my wife eventually took advantage of. (oh yeah, got married in 1979 too; she was not in and never has been in IT, a good thing in the long run I think).
So, the Mortgage System, MTG for short. It was a batch system, in PL/1 but not with flat files or VSAM. Someone earlier in the decade had written a little DBMS system that this and other systems used. It was hierarchical, so each mortgage was a root record and had children records of various types, like for the payments collected; this was the Master File. Transactions for the system were written on custom input sheets that went to the keypunch group. All the transactions were gathered up and run against the Master File overnight. The input transactions would be sorted by Mortgage Number/ID, and the main batch program would process Master and transactions in Number order. It would skip past Mortgages that had no transactions, and then apply the transactions against Master records that did. It ran every other night, which gave the business time to look at output one day and then code new transactions the next day.
As I look back it now, it was a pretty good system. Since it was all batch, looking at info for a Mortgage meant printouts. To save paper, the system used microfiche. A printout for each mortgage was put on fiche to begin with, and then each time a mortgage was updated, all the updated ones would get a new-printout on a new fiche. The fiche was numbered, and there was one fiche that had an index of which number fiche to find a mortgage printout on. That index was recreated after each batch run, and would point to the new fiche as needed. Once a quarter, when a lot of new fiche had been added, the system would print a new set of fiche, and the process would start again. There were also monthly jobs for reports, and an annual run for more reports and some housekeeping, like purging paid-off mortgages from the master.
I suppose everyone has a soft spot for their first system, like their first car (mine was a 68 Ford XL) or other firsts. The system would not last forever, but that is another post...
Next time: Starting to Work
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