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PostgreSQL create table if not exists
...
CREATE TABLE myschema.mytable (i integer);
END IF;
END
$func$;
Call:
SELECT create_mytable(); -- call as many times as you want.
Notes:
The columns schemaname and tablename in pg_tables are case-sensitive. If you double-quote identifiers in the CREATE TABLE statement, you need ...
How can I reverse a NSArray in Objective-C?
...ne. If I see a method that returns an immutable object, I expect it to actually be returning an immutable object. Having it appear to return an immutable object but actual return a mutable object is a dangerous practice to get into.
– Christine
Jul 2 '12 at 22:...
Access-Control-Allow-Origin error sending a jQuery Post to Google API's
I read a lot for the 'Access-Control-Allow-Origin' error, but I don't understand what I have to fix :(
7 Answers
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Can PHP PDO Statements accept the table or column name as parameter?
...DO.
In that case you will simply want to filter and sanitize the data manually. One way to do this is to pass in shorthand parameters to the function that will execute the query dynamically and then use a switch() statement to create a white list of valid values to be used for the table name or col...
How is Racket different from Scheme?
...and not R6RS and not a strict superset of either. I don't think it can be called 'Scheme' because it's not backwards compatible with any Scheme standard.
Most implementations offer extensions, but are otherwise backwards compatible, of course, the compiler that comes with Racket can also run in R5R...
Align image in center and middle within div
...00%; height:100%">
<img src="http://www.garcard.com/images/garcard_symbol.png">
</div>
JSFiddle
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iOS - Dismiss keyboard when touching outside of UITextField
...TapGestureRecognizer(target: self, action: #selector(self.dismissKeyboard (_:)))
self.view.addGestureRecognizer(tapGesture)
For dismissKeyboard
@objc func dismissKeyboard (_ sender: UITapGestureRecognizer) {
aTextField.resignFirstResponder()
}
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What is the difference between `sorted(list)` vs `list.sort()`?
...sorts the list in-place, mutating the list indices, and returns None (like all in-place operations).
sorted() works on any iterable, not just lists. Strings, tuples, dictionaries (you'll get the keys), generators, etc., returning a list containing all elements, sorted.
Use list.sort() when you wa...
Where is PATH_MAX defined in Linux?
Which header file should I invoke with #include to be able to use PATH_MAX as an int for sizing a string?
5 Answers
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Is Javascript a Functional Programming Language?
...e are closures, and higher order functions, does Javascript deserve to be called a Functional Programming language? The main thing I think it lacks is Pure Functions, and it doesn't 'feel' like other functional languages, like lisp (although thats not really a good reason for it not to be a functio...