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Using DISTINCT and COUNT together in a MySQL Query
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use
SELECT COUNT(DISTINCT productId) from table_name WHERE keyword='$keyword'
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Efficient string concatenation in C++
...tor+ is not efficient:
Take a look at this interface:
template <class charT, class traits, class Alloc>
basic_string<charT, traits, Alloc>
operator+(const basic_string<charT, traits, Alloc>& s1,
const basic_string<charT, traits, Alloc>& s2)
You can see t...
What is the difference between an int and an Integer in Java and C#?
...nt is not an object.
int is one of the few primitives in Java (along with char and some others). I'm not 100% sure, but I'm thinking that the Integer object more or less just has an int property and a whole bunch of methods to interact with that property (like the toString() method for example). So...
android get all contacts
... ContactsContract.Contacts.DISPLAY_NAME
} ;
String selection = null; //Selection criteria
String[] selectionArgs = {}; //Selection criteria
String sortOrder = null; //T...
How to create your own library for Android development to be used in every program you write?
...uide focuses on creating Android libraries.
Give your library a name and select a minimum SDK version for the code in the library, then click Finish.
Once the Gradle project sync completes, the library module appears in
the Project panel on the left. If you don't see the new module
fol...
Possible to perform cross-database queries with PostgreSQL?
... executes a query in a remote database
dblink executes a query (usually a SELECT, but it can be any SQL
statement that returns rows) in a remote database.
When two text arguments are given, the first one is first looked up as
a persistent connection's name; if found, the command is executed on
that...
Open file dialog box in JavaScript
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$("#logo").css('opacity','0');
$("#select_logo").click(function(e){
e.preventDefault();
$("#logo").trigger('click');
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<a href="#" ...
Deleting Row in SQLite in Android
...NAME , KAY_LATITUDE , and KEY_LONGITUDE . I want the user to be able to select one and delete it; Can anyone give me a direction to start in? My question is in the actual deletion of the row given only its name.
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How to split one string into multiple strings separated by at least one space in bash shell?
...[*] [a] [*]. Only use it if you are 101% sure that there are no SHELL metacharacters in the splitted string!
– Tino
May 13 '15 at 10:03
4
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AngularJS: how to implement a simple file upload with multipart form?
...tags so you have to do it in a "native-way" that pass the all (eventually) selected files from the user.
controller
$scope.uploadFile = function(files) {
var fd = new FormData();
//Take the first selected file
fd.append("file", files[0]);
$http.post(uploadUrl, fd, {
withCr...