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CREATE TABLE IF NOT EXISTS equivalent in SQL Server [duplicate]
...
if not exists (select * from sysobjects where name='cars' and xtype='U')
create table cars (
Name varchar(64) not null
)
go
The above will create a table called cars if the table does not already exist.
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Double negation (!!) in javascript - what is the purpose? [duplicate]
...good case for it after I posted that. When doing a return from a function and needing a boolean type to be returned and not the object itself, such as: return !!guess; I can see why the earlier usage is not totally necessary. (guess = !!option.guess)
– JoePC
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Java 8 NullPointerException in Collectors.toMap
...ws a NullPointerException if one of the values is 'null'. I don't understand this behaviour, maps can contain null pointers as value without any problems. Is there a good reason why values cannot be null for Collectors.toMap ?
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How to map atan2() to degrees 0-360
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For those not comfortable with this notation, and without the conversion to degrees built in: if(x>0) {radians = x;} else {radians = 2*PI + x;} so we are just adding 2PI to the result if it is less than 0.
– David Doria
Sep 25 '1...
Split string, convert ToList() in one line
I have a string that has numbers
10 Answers
10
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How to escape the % (percent) sign in C's printf?
... this won't work. \045 is compile-time escape that is part of the language and will turn into % when compiled. printf is a run-time function, so it deals with bytes of your string, not with C source code, and it has its own escape sequences that are parts of the function. In short, printf is a "lang...
Converting user input string to regular expression
I am designing a regular expression tester in HTML and JavaScript. The user will enter a regex, a string, and choose the function they want to test with (e.g. search, match, replace, etc.) via radio button and the program will display the results when that function is run with the specified argument...
How do I remove leading whitespace in Python?
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The lstrip() method will remove leading whitespaces, newline and tab characters on a string beginning:
>>> ' hello world!'.lstrip()
'hello world!'
Edit
As balpha pointed out in the comments, in order to remove only spaces from the beginning of the string, lstrip(' ') s...
Simulate limited bandwidth from within Chrome?
... answered Apr 26 '12 at 8:17
Andy DaviesAndy Davies
5,65722 gold badges2323 silver badges2121 bronze badges
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Why is using “for…in” for array iteration a bad idea?
...5;
for (var x in a) {
// Shows only the explicitly set index of "5", and ignores 0-4
console.log(x);
}
/* Will display:
5
*/
Also consider that JavaScript libraries might do things like this, which will affect any array you create:
// Somewhere deep in your JavaScript...