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I'm a young upstart programmer and I've never actually seen a database. But computers in large part come in boxes, not in cylinders so I was wondering why they are always represented as a cylinder when people show their architecture drawings.

Is there a reason why or is it just tradition to draw them like that?

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closed as off topic by Justin Cave, JB King, Jarrod Roberson, gnat, chrisaycock Apr 10 '12 at 14:00


This is an exact duplicate of a question on SO. –  Jerry Coffin Apr 9 '12 at 19:53
because databases are cylinders –  WuHoUnited Apr 10 '12 at 0:25

4 Answers 4

The icon is probably meant to represent an old-school disk pack like this


mainly because databases typically reside on a large random-access device like an HDD.

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I like the way the operator is stroking it :) –  Ian Apr 10 '12 at 12:00

Although I don't have a specific reference to cite, I took it to represent a hard drive. Historically, hard drives store data magnetically on round cylinders. Since databases are all about persistance, hard drives are the mechanism for doing so.

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Because their main purpose is to write data to a cylinder (disk).

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I suppose a platter is a very very short cylinder. –  Dan Ray Apr 9 '12 at 19:55
@DanRay - or you have many platters which resemple a cylinder. –  JeffO Apr 9 '12 at 19:58
Before there were disks, there was drum storage (or drum memory). –  OldFart Apr 9 '12 at 20:07

I've always looked at the icon more as a silo than a cylinder: that is, a large high-volume container that can store loads of grain/salt/data.

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