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How to use count and group by at the same select statement
I have an sql select query that has a group by.
I want to count all the records after the group by statement.
Is there a way for this directly from sql?
For example, having a table with users I want to select the different towns and the total number of users
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What is the difference between Java RMI and RPC?
... a Java based technology and it's object oriented.
With RPC you can just call remote functions exported into a server, in RMI you can have references to remote objects and invoke their methods, and also pass and return more remote object references that can be distributed among many JVM instances, ...
What's the fastest way to do a bulk insert into Postgres?
I need to programmatically insert 10's of millions of records into a postgres database. Presently I am executing 1000's of insert statements in a single "query".
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Alternate background colors for list items
..."link">Link 5</a></li>
</ul>
If your list is dynamically generated, this task would be much easier.
If you don't want to have to manually update this content each time, you could use the jQuery library and apply a style alternately to each <li> item in your list:
<u...
Getting current date and time in JavaScript
...rns a zero-based number so to get the correct month you need to add 1, so calling .getMonth() in may will return 4 and not 5.
So in your code we can use currentdate.getMonth()+1 to output the correct value. In addition:
.getDate() returns the day of the month <- this is the one you want
.getDa...
Detect changed input text box
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This solution is actually far better than using keyup. E.g. IE lets the user clear input field by clicking an X which does not trigger keyup.
– Georg
Dec 29 '13 at 13:24
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Syntax for creating a two-dimensional array
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@Nawaz No, Arrays are Object in java and memory is allocated to Objects only by using new keyword.
– roottraveller
Jun 13 '17 at 9:40
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Which version of Perl should I use on Windows? [closed]
...e repeatedly had with ActiveState is that my modules sometimes fail to install because I need an upgrade to a core module, but they won't allow that. Thus, everybody who doesn't use Windows can use my code, but they can't do that with ActiveState's Perl.
ActiveState also has a very dodgy build sys...
Find index of a value in an array
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int keyIndex = Array.FindIndex(words, w => w.IsKey);
That actually gets you the integer index and not the object, regardless of what custom class you have created
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Changing column names of a data frame
I have a data frame called "newprice" (see below) and I want to change the column names in my program in R.
16 Answers
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