Wikipedia:Reference desk/Archives/Computing/2017 August 15
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August 15
editMemory cost - thumb drive vs. computer
editWhy does a 32GB thumb drive cost $10-12 but 32GB for a computer costs $200 or so? Bubba73 You talkin' to me? 06:47, 15 August 2017 (UTC)
- To a rough approximation, because the one is slow but persistent flash memory while the other is fast but ephemeral DRAM. They are very different things having one property that is measured in the same way. Why does a kg of cheese cost less than a kg of gold? --Stephan Schulz (talk) 09:06, 15 August 2017 (UTC)
- Yes, the better comparison is with hard drive space, where 32 GB is dirt cheap. Think of RAM as adding to the capacity of your brain versus the other as buying enough paper, pencils and erasers to write down that much data. StuRat (talk) 12:48, 15 August 2017 (UTC)
- So basically they are simply two types of similiar things - the computer memory is much faster. Bubba73 You talkin' to me? 14:56, 15 August 2017 (UTC)
- And it has different addressing, and it has unlimited write cycles, and so on. --Stephan Schulz (talk) 15:16, 15 August 2017 (UTC)
Thanks for the answers. Bubba73 You talkin' to me? 20:50, 15 August 2017 (UTC)
storing digital data in crystals
editHas there been any research on storing digital data in crystals? — Preceding unsigned comment added by 52.8.172.72 (talk) 10:56, 15 August 2017 (UTC)
- Yes. It has been going on for a long time. University of Southampton made a news splash last year with their "Superman" crystals. 209.149.113.5 (talk) 12:41, 15 August 2017 (UTC)
- Holographic memory uses a crystal to store the holographic data which is written and read with a laser.
Sleigh (talk) 19:37, 15 August 2017 (UTC)
Any way to get a "stacked by" view in Windows Explorer in Windows 7?
editIn the old Windows Vista, the Windows Explorer (file browser) had a "stacked by" view, which would dynamically organize the objects in a folder according to file properties. Using the feature, all the objects in a folder and its sub-folders could, for example, be regrouped into virtual folders by file type. This feature was removed in Windows 7. Is there a way to simulate the functionality in Windows 7? --134.242.92.97 (talk) 19:28, 15 August 2017 (UTC)
Tools to evaluate normalization using queries?
editOur article on the first normal form notes that it requires that all columns be atomic, but that the atomicity of a column can depend on how it is used (e.g. a multi-line postal address field used only to print mailing labels vs. one used to count customers per postal code). Do any tools exist that can test what normal forms a database probably does and doesn't satisfy, based on the queries that are run against it (e.g. treating substring queries as evidence against first normal form)? NeonMerlin 20:33, 15 August 2017 (UTC)
- I am not sure that I understand the question if the question is about a tool. It has always seemed to me that first normal form is really a matter of the database designer knowing what the repeating items are and setting up proper many-to-one relationships. A spreadsheet is not a database, for instance. Do you have a specific question about how to use a tool? Robert McClenon (talk) 04:25, 17 August 2017 (UTC)
- MSAccess includes its specialized Visual Basic for Applications (VBA) and has several text functions to have users use builtin or programming the own functions for all kind of customized data normalizing. Microsoft SQL Server has an free Edition, called Microsoft SQL Server Express and contain some normalizing functions. There's less programming functionality, but a VIEW can also be written and used as a virtual table, similar to a query. Both and also LibreOffice Base allow user to draw queries in a table diagram. Most differences are found in the way to visualize properties of joins. --Hans Haase (有问题吗) 22:38, 18 August 2017 (UTC)