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“Prevent saving changes that require the table to be re-created” negative effects
...new column
Change the Allow Nulls setting for a column
Change the column order in the table
Change the column data type
Using ALTER is safer, as in case the metadata is lost while you re-create the table, your data will be lost.
...
Checking for an empty field with MySQL
...er late to this discussion, but the statement will work if you reverse the order: "AND ((email IS NOT NULL) AND (email != '')). If evaluated in the other order, the statement evaluates as null (not TRUE) if the email address is NULL, and thus will not be either TRUE or FALSE. So the IS NULL check...
Why is the Windows cmd.exe limited to 80 characters wide?
I love stretching my terminal on unix. What is the history or reason behind windows lame command line?
14 Answers
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How do you split and unsplit a window/view in Eclipse IDE?
... The key is to drag the new opened editor to reach the bottom border of the old editor, then a black arrow and a black line at the middle of the old editor will appear to indicate that you split the editor successfully.
– zhihong
Sep 26 '13 at 13:35...
How to determine a Python variable's type?
...I see the type of a variable whether it is unsigned 32 bit, signed 16 bit, etc.?
17 Answers
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How do I check if a given string is a legal/valid file name under Windows?
..., LPT1, LPT2, LPT3, LPT4, LPT5, LPT6, LPT7, LPT8, LPT9 (and avoid AUX.txt, etc)
The file name is all periods
Some optional things to check:
File paths (including the file name) may not have more than 260 characters (that don't use the \?\ prefix)
Unicode file paths (including the file name) with...
Create a dictionary with list comprehension
...for k, v in blahs}
And we see that it worked, and should retain insertion order as-of Python 3.7:
>>> mydict
{'blah0': 'blah', 'blah1': 'blah', 'blah2': 'blah', 'blah3': 'blah'}
In Python 2 and up to 3.6, order was not guaranteed:
>>> mydict
{'blah0': 'blah', 'blah1': 'blah', 'bl...
Using only CSS, show div on hover over
...his answer doesn't require that you know the what type of display (inline, etc.) the hideable element is supposed to be when being shown:
.hoverable:not(:hover) + .show-on-hover {
display: none;
}
<a class="hoverable">Hover over me!</a>
<div class="show-on-hover">I'm a...
Getting the closest string match
...ittle deeper into analysing the tokens of a phrase a bit more, that is the order/positions of the phrase tokens, non-query token sequences and it accepts a bit more fuzziness when it comes to something like "acbd" compared to "abcd". Tendency of the phrase_value scores equals yours, but get a bit lo...
What's a “static method” in C#?
...) { return 1; }
public static int StaticMethod() { return 42; }
}
In order to call InstanceMethod, you need an instance of the class:
SomeClass instance = new SomeClass();
instance.InstanceMethod(); //Fine
instance.StaticMethod(); //Won't compile
SomeClass.InstanceMethod(); //Won't co...