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Best way to test for a variable's existence in PHP; isset() is clearly broken
...l scope variables as well, on can do a $defined_vars = get_defined_vars(); and then test via array_key_exists('v', $defined_vars);.
– Henrik Opel
Sep 27 '10 at 16:01
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Liquibase lock - reasons?
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There is a built-in command in Liquibase called releaseLocks that would execute what @Adrian Ber answered but I think it is database agnostic.
– user1434769
Oct 26 '15 at 11:17
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Common MySQL fields and their appropriate data types
...g up a very small MySQL database that stores, first name, last name, email and phone number and am struggling to find the 'perfect' datatype for each field. I know there is no such thing as a perfect answer, but there must be some sort of common convention for commonly used fields such as these. For...
Should image size be defined in the img tag height/width attributes or in CSS? [duplicate]
...better coding practice to define an images size in the img tag's width and height attributes?
7 Answers
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Is there a “do … until” in Python? [duplicate]
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BTW, this is called "loop-and-a-half". Python continues to support this construct because it's one of the easiest loop patterns to correctly write and understand. See cs.duke.edu/~ola/patterns/plopd/loops.html#loop-and-a-half
– B...
Sending websocket ping/pong frame from browser
...gn pattern (e.g. I literally send "ping" or any other string to the server and have it respond). Is ping-pong at all related to continuation frames?
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In which scenario do I use a particular STL container?
...p on STL containers in my book on C++, specifically the section on the STL and its containers. Now I do understand each and every one of them have their own specific properties, and I'm close to memorizing all of them... But what I do not yet grasp is in which scenario each of them is used.
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What's the difference between a web site and a web application? [closed]
I'm stumped trying to come up to a difference between a website and a web application for myself. As I see it, a web site points to a specific page and a web application is more of some sort of 'portal' to content and information.
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How can I check whether a numpy array is empty or not?
...an always take a look at the .size attribute. It is defined as an integer, and is zero (0) when there are no elements in the array:
import numpy as np
a = np.array([])
if a.size == 0:
# Do something when `a` is empty
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How do I parse command line arguments in Bash?
...as non-opt/last argument:
#93.184.216.34 example.com
To better understand ${i#*=} search for "Substring Removal" in this guide. It is functionally equivalent to `sed 's/[^=]*=//' <<< "$i"` which calls a needless subprocess or `echo "$i" | sed 's/[^=]*=//'` which calls two needless subp...