11-08-2011, 12:05 PM | #1 |
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Question about date sorting
If I understand correctly ...
The "Date" (date added) column sorts on the underlying datetime, not on the visible date. But sometimes I want to use this in a nested sort, say Title within Author within Date -- which doesn't work, because I'll just get everything sorted by Date to the (milli)second. I created a composite column ("{date}"), and that sorted nicely, but I took a whopping performance hit (see here ). So I'm wondering if I overlooked an option that doesn't require the use of a composite column ... |
11-08-2011, 02:30 PM | #2 |
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Regarding your post in the date-changed thread: I have an implementation that sorts dates as displayed. The performance penalty is not huge. For a 20,000 book library, the time to sort by a date column went from approximately 1/2 second to 1 second, or some 500 microseconds per book. This is consistent with my mark 1 eyeball estimate of the cost of trimming the date.
Next step is for Kovid to look at it. I might have done something stupid, he might have some suggestions for improvement, or he might object to the principle for a reason I haven't thought of. One note: the sort will respect strange display templates and do something. If your display template is, for example yyyy/ss, then the month, day, hour, and minute will be filled in with a constant. The results could easily not be what you expect. Continuing the example, 2011/10/25 19:08:10 and 2011/01/19 10:10:10 will sort as equal because the years (2011) and the seconds (10) match. Last edited by chaley; 11-08-2011 at 02:53 PM. Reason: fix typo pointed out by starson17 |
11-08-2011, 02:52 PM | #3 |
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11-08-2011, 02:53 PM | #4 |
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11-08-2011, 02:57 PM | #5 |
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11-08-2011, 02:59 PM | #6 |
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See http://www.urbandictionary.com/defin...=Neener-neener. No idea what the etymology is.
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11-08-2011, 03:00 PM | #7 |
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That makes a lot of sense -- and saves me a big perfomance hit since I don't have to use a composite column! p.s. I'd already quoted it but got distracted while you fast fingered guys chatted |
11-08-2011, 03:28 PM | #8 | ||
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Quote:
Quote:
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11-09-2011, 04:44 AM | #9 |
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The change mentioned in post #2 will be in the next release. Users must change a tweak to enable it.
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