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Concatenating two lists - difference between '+=' and extend()
... Maybe the difference has more implications when it comes to ducktyping and if your maybe-not-really-a-list-but-like-a-list supports .__iadd__()/.__add__()/.__radd__() versus .extend()
– Nick T
Dec 15 '14 at 22:21
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UPDATE multiple tables in MySQL using LEFT JOIN
I have two tables, and want to update fields in T1 for all rows in a LEFT JOIN.
5 Answers
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MySQL Select Date Equal to Today
I'm trying to run a mysql select statement where it looks at today's date and only returns results that signed up on that current day. I've currently tried the following, but it doesn't seem to work.
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Setting design time DataContext on a Window is giving a compiler error?
... runtime.
mc:Ignorable can be given a space-delimited list of namespaces, and mc:ProcessContent can be given a space-delimited list of elements. When XamlXmlReader encounters ignorable content that can’t be resolved, it doesn’t report any nodes for it. If the ignorable content can be resolved, ...
How does the bitwise complement operator (~ tilde) work?
...representation of a number, taking its complement (inverting all the bits) and adding one. Two starts as 0000 0010, and by inverting the bits we get 1111 1101. Adding one gets us the result above. The first bit is the sign bit, implying a negative.
So let's take a look at how we get ~2 = -3:
Here's ...
Django removing object from ManyToMany relationship
...jango's Relations Docs
Note: you might have to get an instance of my_mood and my_interest using Django's QuerySet API before you can execute this code.
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Where does Scala look for implicits?
...bout the latter type, if one calls a method m on an object o of a class C, and that class does not support method m, then Scala will look for an implicit conversion from C to something that does support m. A simple example would be the method map on String:
"abc".map(_.toInt)
String does not supp...
How to vertically align into the center of the content of a div with defined width/height?
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I have researched this a little and from what I have found you have four options:
Version 1: Parent div with display as table-cell
If you do not mind using the display:table-cell on your parent div, you can use of the following options:
.area{
height...
Why does PostgreSQL perform sequential scan on indexed column?
...Also, a sequential scan can request several pages from the heap at a time, and ask the kernel to be fetching the next chunk while it works on the current one- an index scan fetches one page at once. (A bitmap scan does a compromise between the two, you usually see that appearing in a plan for querie...
Is there a builtin confirmation dialog in Windows Forms?
...ike to create a simple confirm dialog saying "Please check the information and if you're sure it's correct, click OK."
3 An...