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Python `if x is not None` or `if not x is None`?
... of the if not x is None version to be more clear, but Google's style guide and PEP-8 both use if x is not None . Is there any minor performance difference (I'm assuming not), and is there any case where one really doesn't fit (making the other a clear winner for my convention)?*
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PostgreSQL Connection URL
... postgresql://localhost/mydb?user=other&password=secret did the trick
– Karuhanga
Oct 29 '18 at 14:31
1
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Is there a CSS selector by class prefix?
...us-"] will match the following element, which may be undesirable:
<div id='D' class='foo-class foo-status-bar bar-class'></div>
If you can ensure that such a scenario will never happen, then you are free to use such a selector for the sake of simplicity. However, the combination above...
What happens to git commits created in a detached HEAD state?
...herry-pick [SHA] to move the commit onto an existing branch in case you accidentally committed while in detached head state
– Jan Aagaard Meier
Aug 20 '14 at 12:56
3
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Facebook share link without JavaScript
...parameter. You can use an indirect way to achieve this.
Create a server side page for example: "/sharer.aspx"
Link this page whenever you want the share functionality.
In the "sharer.aspx" get the refering url, and redirect user to "https://www.facebook.com/sharer/sharer.php?u={referer}"
Example...
Javascript Equivalent to PHP Explode()
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Downvoter: "How dare you provide a simpler and more performant solution instead of validating my preconceptions??"
– jchook
May 18 '18 at 19:36
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Command line for looking at specific port
... Also worth mentioning the -o flag (i.e. -nao here) to include the PID of the process using the port.
– Steve Chambers
Nov 28 '17 at 10:29
add a comment
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Should I put the Google Analytics JS in the or at the end of ?
... to fix. Imagine someone steps in your store, only to realize that the outside misled them into entering. You'd want to go correct your advertising to fix that.
– Optimus
Sep 9 '17 at 11:40
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Is it possible to make the -init method private in Objective-C?
I need to hide (make private) the -init method of my class in Objective-C.
9 Answers
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In MySQL queries, why use join instead of where?
... in the WHERE clause
SELECT *
FROM TABLE_A a,
TABLE_B b
WHERE a.id = b.id
Here's the query re-written using ANSI-92 JOIN syntax:
SELECT *
FROM TABLE_A a
JOIN TABLE_B b ON b.id = a.id
From a Performance Perspective:
Where supported (Oracle 9i+, PostgreSQL 7.2+, MySQL 3.23+, SQ...