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How to add column if not exists on PostgreSQL?
...when x column doesn't exist ? I found only solution here how to check if column exists.
11 Answers
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AngularJS : Prevent error $digest already in progress when calling $scope.$apply()
...ves. Even though you think it fixed something, it didn't.
You can check if a $digest is already in progress by checking $scope.$$phase.
if(!$scope.$$phase) {
//$digest or $apply
}
$scope.$$phase will return "$digest" or "$apply" if a $digest or $apply is in progress. I believe the differenc...
What is “assert” in JavaScript?
...ing some library that provides one. The usual meaning is to throw an error if the expression passed into the function is false; this is part of the general concept of assertion checking. Usually assertions (as they're called) are used only in "testing" or "debug" builds and stripped out of productio...
Checking if object is empty, works with ng-show but not from controller?
...way, ng-show should keep working, and in your controller you can just do:
if ($scope.items) {
// items have value
} else {
// items is still null
}
And in your $http callbacks, you do the following:
$http.get(..., function(data) {
$scope.items = {
data: data,
// other...
Effective way to find any file's Encoding
...s determining a file's endianness, by analyzing its byte order mark (BOM). If the file does not have a BOM, this cannot determine the file's encoding.
*UPDATED 4/08/2020 to include UTF-32LE detection and return correct encoding for UTF-32BE
/// <summary>
/// Determines a text file's encoding...
PDO mysql: How to know if insert was successful
...
No more like this, $value = $stmt->execute(); if($value){//true}else{//false}
– Ólafur Waage
Jun 3 '11 at 8:40
23
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Check if an element is a child of a parent
...
If you are only interested in the direct parent, and not other ancestors, you can just use parent(), and give it the selector, as in target.parent('div#hello').
Example: http://jsfiddle.net/6BX9n/
function fun(evt) {
va...
Ternary operation in CoffeeScript
...everything is an expression, and thus results in a value, you can just use if/else.
a = if true then 5 else 10
a = if false then 5 else 10
You can see more about expression examples here.
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Does the ternary operator exist in R?
... asks, is there a control sequence in R similar to C's ternary operator ? If so, how do you use it? Thanks!
7 Answers
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Using C# to check if string contains a string in string array
I want to use C# to check if a string value contains a word in a string array. For example,
29 Answers
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