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What exactly are iterator, iterable, and iteration?
What is the most basic definition of "iterable", "iterator" and "iteration" in Python?
13 Answers
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Why start an ArrayList with an initial capacity?
...t 8 elements. Insert one (cost: 1). Insert two -- double, copy one element and insert two (cost: 2). Insert three -- double, copy two elements, insert three (cost: 3). Insert four (cost: 1). Insert five -- double, copy four elements, insert five (cost: 5). Insert six, seven and eight (cost: 3). Tota...
How to select rows that have current day's timestamp?
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use DATE and CURDATE()
SELECT * FROM `table` WHERE DATE(`timestamp`) = CURDATE()
I guess using DATE still uses INDEX.
see the execution plan on the DEMO
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Can't connect Nexus 4 to adb: unauthorized
I have a Nexus 4 with Android 4.3 and I am trying to connect the device to a computer with Windows 7 64bit.
26 Answers
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How do you test that a Python function throws an exception?
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I'm using Python 2.7.10, and the above doesn't work; context.exception does not give the message; it is a type.
– LateCoder
Feb 25 '16 at 16:55
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PostgreSQL function for last inserted ID
...an id column created with the SERIAL pseudo-type. To avoid relying on this and to feel more clean, you can use instead pg_get_serial_sequence:
INSERT INTO persons (lastname,firstname) VALUES ('Smith', 'John');
SELECT currval(pg_get_serial_sequence('persons','id'));
Caveat: currval() only work...
Conversion of a datetime2 data type to a datetime data type results out-of-range value
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I changed my datacolumns and used typeof now... Further I found my problem. there was 1 datarow that contained a wrong date, which triggered the error
– Gerbrand
Aug 26 '09 at 5:46
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Maven: How to include jars, which are not available in reps into a J2EE project?
...l repository. If you create a script with a Maven invocation for each file and keep it alongside the jars, you (and anyone else with access) can easily install the jars (and associated pom files) to their local repository.
For example:
mvn install:install-file -Dfile=/usr/jars/foo.jar -DpomFile=/u...
Logical Operators, || or OR?
... no "better" but the more common one is ||. They have different precedence and || would work like one would expect normally.
See also: Logical operators (the following example is taken from there):
// The result of the expression (false || true) is assigned to $e
// Acts like: ($e = (false || true...
iOS 7 style Blur view
...u being able to capture the view behind the one you're presenting, though, and may have trouble with views that animate behind this content. The need to take a trip through Core Graphics to rasterize the background view will slow things down, so we probably don't have sufficiently direct access to b...