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MySql Table Insert if not exist otherwise update
...since it's the unique key, so it should not change. You do need to include all of the other columns from your table. You can use the VALUES() function to make sure the proper values are used when updating the other columns.
Here is your update re-written using the proper INSERT ... ON DUPLICATE KEY...
How to reset sequence in postgres and fill id column with new data?
... This might cause duplicate ids. To prevent this, you can first set all to very high values: UPDATE t SET idcolumn=1000000+ nextval('seq'); then run the above script.
– tahagh
Nov 28 '13 at 13:15
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How do I replace NA values with zeros in an R dataframe?
...then assign it to the location/name on the left. In this case, we aren't really "doing" anything - just making zeroes. The left side is saying: look at the d object, inside the d object (the square brackets), find all the elements that return TRUE (is.na(d) returns a logical for each element). Once...
How to unzip files programmatically in Android?
I need a small code snippet which unzips a few files from a given .zip file and gives the separate files according to the format they were in the zipped file. Please post your knowledge and help me out.
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What difference is there between WebClient and HTTPWebRequest classes in .NET?
...FtpWebRequest, depend on your request. Below is an example:
Example:
var _request = (HttpWebRequest)WebRequest.Create("http://stackverflow.com");
var _response = (HttpWebResponse)_request.GetResponse();
WebClient
System.Object
System.MarshalByRefObject
System.ComponentModel....
How to allow to accept only image files?
...t is very sketchy on mobiles (as of 2015) and by some reports this may actually prevent some mobile browsers from uploading anything at all, so be sure to test your target platforms well.
For detailed browser support, see http://caniuse.com/#feat=input-file-accept
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New lines inside paragraph in README.md
... to ensure that each line ends with two spaces. So, change
a
b
c
into
a__
b__
c
(where _ is a blank space).
Or, you can add explicit <br /> tags.
a <br />
b <br />
c
share
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How to get first element in a list of tuples?
...
do you mean something like this?
new_list = [ seq[0] for seq in yourlist ]
What you actually have is a list of tuple objects, not a list of sets (as your original question implied). If it is actually a list of sets, then there is no first element because set...
Ask for User Permission to Receive UILocalNotifications in iOS 8
...serNotificationCategory()
notificationCategory.identifier = "INVITE_CATEGORY"
notificationCategory.setActions([replyAction], forContext: UIUserNotificationActionContext.Default)
//registerting for the notification.
application.registerUserNotificationSettings(UIUserN...
PHP global in functions
...ngletons, registries, constants). You do not want to use them. A function call should not have to rely on anything outside, e.g.
function fn()
{
global $foo; // never ever use that
$a = SOME_CONSTANT // do not use that
$b = Foo::SOME_CONSTANT; // do not use that unl...