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What's the difference between NOT EXISTS vs. NOT IN vs. LEFT JOIN WHERE IS NULL?
... NULL is less efficient
In PostgreSQL, NOT IN is less efficient
In Oracle, all three methods are the same.
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Differences between Java 8 Date Time API (java.time) and Joda-Time
...s perfect ;-)).
c) With both libraries we get a real calendar date type (called LocalDate), a real wall time type (called LocalTime) and the composition (called LocalDateTime). That is a very big win compared with old java.util.Calendar and java.util.Date.
d) Both libraries use a method-centric ap...
MySQL 'create schema' and 'create database' - Is there any difference
... CREATE SCHEMA is a synonym for CREATE DATABASE as of MySQL 5.0.2.
this all goes back to an ANSI standard for SQL in the mid-80s.
That standard had a "CREATE SCHEMA" command, and it served to introduce
multiple name spaces for table and view names. All tables and views were
created within a "s...
Get application version name using adb
...y package I have tried to look up on my tablet (android 2.2). On my phone all the version information is there (android 2.3).
– frognosis
Aug 13 '12 at 23:08
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Find nearest value in numpy array
...f you can't assume that the array is already sorted. It’s overkill for small arrays, but once they get large this is much faster.
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Convert to absolute value in Objective-C
...), fabsf(float), fabs(double), or fabsl(long double).
Those functions are all part of the C standard library, and so are present both in Objective-C and plain C (and are generally available in C++ programs too.)
(Alas, there is no habs(short) function. Or scabs(signed char) for that matter...)
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Different floating point result with optimization enabled - compiler bug?
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Intel x86 processors use 80-bit extended precision internally, whereas double is normally 64-bit wide. Different optimization levels affect how often floating point values from CPU get saved into memory and thus rounded from 80-bit precision to 64-bit precision.
Use the -ffloat-st...
When to use , tag files, composite components and/or custom components?
...nces be the only solution when a composite component doesn't suffice. Generally, having an <ui:include> with one or more <ui:param> which passes a managed bean property (and thus not a hardcoded value) is a signal that the include file can better be a tag file.
Examples:
How to create a...
“git pull” or “git merge” between master and development branches
...nges. I need to merge changes from master into develop , but will eventually merge everything from develop into master . I have two different workflows in mind:
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Google Play Services Library update and missing symbol @integer/google_play_services_version
...project to the latest version of Google Play Services ( v4.0, released on Halloween 2013 ), you are now supposed to add a new tag into the AndroidManifest.xml file.
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