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How to select distinct rows in a datatable and store into an array
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DataView view = new DataView(table);
DataTable distinctValues = view.ToTable(true, "Column1", "Column2" ...);
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What are the best practices for using a GUID as a primary key, specifically regarding performance?
...rimary Key. Honestly, I haven't seen any problem, but I'm about to start a new application and I still want to use the GUIDs as the Primary Keys, but I was thinking of using a Composite Primary Key (The GUID and maybe another field.)
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What do the &,
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Should IBOutlets be strong or weak under ARC?
...ple is for IBOutlets to be strong unless weak is specifically needed to avoid a retain cycle. As Johannes mentioned above, this was commented on in the "Implementing UI Designs in Interface Builder" session from WWDC 2015 where an Apple Engineer said:
And the last option I want to point out is t...
How to port data-only volumes from one host to another?
...ed tar file of all the files in the /data directory
RESTORE:
# create a new data container
$ sudo docker create -v /data --name DATA2 busybox true
# untar the backup files into the new container᾿s data volume
$ sudo docker run --rm --volumes-from DATA2 -v $(pwd):/backup busybox tar xvf /backup/...
Find element's index in pandas Series
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I'm impressed with all the answers here. This is not a new answer, just an attempt to summarize the timings of all these methods. I considered the case of a series with 25 elements and assumed the general case where the index could contain any values and you want the index value...
Sending images using Http Post
...l, List<NameValuePair> nameValuePairs) {
HttpClient httpClient = new DefaultHttpClient();
HttpContext localContext = new BasicHttpContext();
HttpPost httpPost = new HttpPost(url);
try {
MultipartEntity entity = new MultipartEntity(HttpMultipartMode.BROWSER_COMPATIBLE);...
How to compile and run C/C++ in a Unix console/Mac terminal?
...ules propagated to targets specified when invoking make. Learned something new today =)
– Branan
Oct 21 '08 at 17:04
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jQuery .on('change', function() {} not triggering for dynamically created inputs
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You should provide a selector to the on function:
$(document).on('change', 'input', function() {
// Does some stuff and logs the event to the console
});
In that case, it will work as you expected. Also, it is better to specify some el...
C++ semantics of `static const` vs `const`
...t to be clear, C++0x doesn't remove that particular use of const, but the new constexpr can be used instead (and in other scenarios as well). Actually, the C++0x standard expands the ability to use const in that scenario to non-integral "literal types" as well. I think I'd prefer using constexpr f...