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django order_by query set, ascending and descending
...spect that it be more efficient to let the SQL server handle the order, at least in theory. It's nice and clear, though.
– Michael Scheper
Sep 26 '16 at 16:51
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Specify multiple attribute selectors in CSS
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You have to indeed (at least for the moment), unless you use preprocessors. Consult this thread for more details.
– raina77ow
Sep 25 '16 at 9:09
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How to set initial size of std::vector?
..., so you can insert (up to) that many without it having to reallocate.
At least in my experience, it's fairly unusual for either of these to make a huge difference in performance--but either can affect correctness under some circumstances. In particular, as long as no reallocation takes place, iter...
Can you have multiline HTML5 placeholder text in a ?
...88.7% of currently (Oct 2015) used browsers.
Update: Today, it works on at least 94.4% of currently (July 2018) used browsers.
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Data Modeling with Kafka? Topics and Partitions
...sages and the total number of partitions in a broker cluster need to be at least the same as the number of consumers in a consumer group to make sense of the partitioning feature. Consumers in a consumer group will split the burden of processing the topic between themselves according to the partitio...
How should I use try-with-resources with JDBC?
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There's no need for the outer try in your example, so you can at least go down from 3 to 2, and also you don't need closing ; at the end of the resource list. The advantage of using two try blocks is that all of your code is present up front so you don't have to refer to a separate method:...
How to sign an android apk file
...apk
s = signature was verified
m = entry is listed in manifest
k = at least one certificate was found in keystore
i = at least one certificate was found in identity scope
jar verified.
Warning:
This jar contains entries whose certificate chain is not validated.
This jar contains signatures ...
COUNT(*) vs. COUNT(1) vs. COUNT(pk): which is better? [duplicate]
...vial so gives the same plan. A PK is unique and non-null (in SQL Server at least) so COUNT(PK) = COUNT(*)
This is a similar myth to EXISTS (SELECT * ... or EXISTS (SELECT 1 ...
And see the ANSI 92 spec, section 6.5, General Rules, case 1
a) If COUNT(*) is specified, then the result is the...
Can you determine if Chrome is in incognito mode via a script?
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This is the least hack-ish way and should be at the top. Clean and elegant.
– Tom Teman
Oct 4 '15 at 16:21
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Regexp Java for password validation
... # start-of-string
(?=.*[0-9]) # a digit must occur at least once
(?=.*[a-z]) # a lower case letter must occur at least once
(?=.*[A-Z]) # an upper case letter must occur at least once
(?=.*[@#$%^&+=]) # a special character must occur at least once
(?=\S+$) ...