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Why is a database always represented with a cylinder?

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Re: Why is a database always represented with a cylinder?

#3
I do not find that answer convincing. Both drum memory (https://en.wikipedia.org/wiki/Drum_memory) and mercury delay line memory (https://en.wikipedia.org/wiki/Delay-line_memory#Mercury_dela...) were used as primary memory, not for storage.

In addition mercury delay lines lost their data when unpowered.

My money would be on https://en.wikipedia.org/wiki/Disk_pack. Those are objects that people carried around to move data (http://www.catb.org/esr/writings/taoup/html/ch02s01.html: Ken Thompson quietly began answering requests by shipping out tapes and disk packs — each, according to legend, with a note signed “love, ken”)

Call it the floppy disk of the 1970s

Re: Why is a database always represented with a cylinder?

#4
post #3

I do not find that answer convincing. Both drum memory ( https://en.wikipedia.org/wiki/Drum_memory ) and mercury delay line memory ( https://en.wikipedia.org/wiki/Delay-line_memory#Mercury_dela... ) were used as primary memory, not for storage. In addition mercury delay lines lost their data when unpowered. My money would be on https://en.wikipedia.org/wiki/Disk_pack . Those are objects that people carried around to…

I came to the same conclusion from the fact that a typical database icon looks a lot more like a disk pack, with its smooth sides, than like drum memory.

Re: Why is a database always represented with a cylinder?

#6
post #3

I do not find that answer convincing. Both drum memory ( https://en.wikipedia.org/wiki/Drum_memory ) and mercury delay line memory ( https://en.wikipedia.org/wiki/Delay-line_memory#Mercury_dela... ) were used as primary memory, not for storage. In addition mercury delay lines lost their data when unpowered. My money would be on https://en.wikipedia.org/wiki/Disk_pack . Those are objects that people carried around to…

Right, the icon is a stack of disk packs in their protective covers.