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Possibility of duplicate Mongo ObjectId's being generated in two different collections?
...que ID (please let me know if there are more):
Before this discussion, recall that the BSON Object ID consists of:
[4 bytes seconds since epoch, 3 bytes machine hash, 2 bytes process ID, 3 bytes counter]
Here are the three possibilities, so you judge for yourself how likely it is to get a dupe:
...
Make Bootstrap Popover Appear/Disappear on Hover instead of Click
...r data-attributes ? Even if I use data-attributes, I still would have to call $("#popover").popover(); from my JavaScript.
– Bailey
Jan 3 '18 at 7:58
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Objective-C declared @property attributes (nonatomic, copy, strong, weak)
... retaining the copy.
Assign
Assign is somewhat the opposite to copy. When calling the getter of an assign property, it returns a reference to the actual data. Typically you use this attribute when you have a property of primitive type (float, int, BOOL...)
Retain
retain is required when the attribut...
Why can't I use the 'await' operator within the body of a lock statement?
The await keyword in C# (.NET Async CTP) is not allowed from within a lock statement.
8 Answers
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Check if a user has scrolled to the bottom
...ight of the visible window and checks if that equals the height of the overall content (document). If you wanted to instead check if the user is near the bottom, it'd look something like this:
$(window).scroll(function() {
if($(window).scrollTop() + $(window).height() > $(document).height() ...
Dashed line border around UIView
...t@2x.png and test@3x.png with size of 240x240 and 360x360 which is used in all the apple device automatically with it's related name. (i.e. test.png is use in iPhone 4, test@2x will useful for iPhone 4s, 5, 5s, 6, 6s and twst@3x will useful for iPhone 6 plus, 6s plus.
– Paras J...
What is the difference between char, nchar, varchar, and nvarchar in SQL Server?
...torage space for number of characters you specify even if you don't use up all that space.
varchar and nvarchar are variable-length which will only use up spaces for the characters you store. It will not reserve storage like char or nchar.
nchar and nvarchar will take up twice as much storage spac...
CORS Access-Control-Allow-Headers wildcard being ignored?
...
Support for wildcards in the Access-Control-Allow-Headers header was added to the living standard only in May 2016, so it may not be supported by all browsers. On browser which don't implement this yet, it must be an exact match: https://www.w3.org/TR/2014/REC-cors-201...
How to send an email from JavaScript
...ject=subject&body=body');
Another solution would be to do an ajax call to your server, so that the server sends the email. Be careful not to allow anyone to send any email through your server.
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Cannot delete or update a parent row: a foreign key constraint fails
... (`advertiser_id`)
REFERENCES `jobs` (`advertiser_id`);
...is actually the opposite to what it should be. As it is, it means that you'd have to have a record in the jobs table before the advertisers. So you need to use:
ALTER TABLE `jobs`
ADD CONSTRAINT `advertisers_ibfk_1` FOREIGN KEY...