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Foreign Key to non-primary key
I have a table which holds data, and one of those rows needs to exist in another table. So, I want a foreign key to maintain referential integrity.
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$(window).scrollTop() vs. $(document).scrollTop()
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@d2burke scrollTop() is a getter and scrollTop(value) is a setter. scrollTop() without arguments does not change the scroll position.
– user1107907
Feb 19 '15 at 22:20
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leading zeros in rails
I have fields hr and min , both integers in my application. For hr field, if the user enters "1" I would like Rails to automatically pad it to "01" before saving it to the database. Also for the min field if the user enter "0" it should put in as "00".
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Overlaying histograms with ggplot2 in R
I am new to R and am trying to plot 3 histograms onto the same graph.
Everything worked fine, but my problem is that you don't see where 2 histograms overlap - they look rather cut off.
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How to Query an NTP Server using C#?
... ntpData = new byte[48];
//Setting the Leap Indicator, Version Number and Mode values
ntpData[0] = 0x1B; //LI = 0 (no warning), VN = 3 (IPv4 only), Mode = 3 (Client Mode)
var addresses = Dns.GetHostEntry(ntpServer).AddressList;
//The UDP port number assigned to NTP is 123
var ...
Strange, unexpected behavior (disappearing/changing values) when using Hash default value, e.g. Hash
...ior applies to any default value that is subsequently mutated (e.g. hashes and strings), not just arrays.
TL;DR: Use Hash.new { |h, k| h[k] = [] } if you want the most idiomatic solution and don’t care why.
What doesn’t work
Why Hash.new([]) doesn’t work
Let’s look more in-depth at why...
How to format strings in Java
...g.format, also take a look java.text.MessageFormat. The format less terse and a bit closer to the C# example you've provided and you can use it for parsing as well.
For example:
int someNumber = 42;
String someString = "foobar";
Object[] args = {new Long(someNumber), someString};
MessageForma...
How to implement WiX installer upgrade?
...omatic upgrades. It prevents downgrades, giving a localised error message, and also prevents upgrading an already existing identical version (i.e. only lower versions are upgraded):
<MajorUpgrade
AllowDowngrades="no" DowngradeErrorMessage="!(loc.NewerVersionInstalled)"
AllowSameVersionUp...
How to watch for array changes?
...-based assignment? I want something that would fire an event that I could handle.
10 Answers
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mongo - couldn't connect to server 127.0.0.1:27017
I am coming from riak and redis where I never had an issue with this services starting, or to interact.
38 Answers
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