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How to find duplicates in 2 columns not 1
...composite key between the two fields. This will require a unique stone_id and upcharge_title for each row.
As far as finding the existing duplicates try this:
select stone_id,
upcharge_title,
count(*)
from your_table
group by stone_id,
upcharge_title
having coun...
How can I permanently enable line numbers in IntelliJ?
...log is slightly different, a General submenu has been added between Editor and Appearance as shown below
IntelliJ 8.1.2 - 13.X
From IntelliJ 8.1.2 onwards, this option is in File | Settings1. Within the IDE Settings section of that dialog, you'll find it under Editor | Appearance.
On a Mac, th...
Double vs. BigDecimal?
I have to calculate some floating point variables and my colleague suggest me to use BigDecimal instead of double since it will be more precise. But I want to know what it is and how to make most out of BigDecimal ?
...
What are dictionary view objects?
...sentially what their name says: views are simply like a window on the keys and values (or items) of a dictionary. Here is an excerpt from the official documentation for Python 3:
>>> dishes = {'eggs': 2, 'sausage': 1, 'bacon': 1, 'spam': 500}
>>> keys = dishes.keys()
>>>...
How can I delete a query string parameter in JavaScript?
... better way to delete a parameter from a query string in a URL string in standard JavaScript other than by using a regular expression?
...
Named string formatting in C#
...
There is no built-in method for handling this.
Here's one method
string myString = "{foo} is {bar} and {yadi} is {yada}".Inject(o);
Here's another
Status.Text = "{UserName} last logged in at {LastLoginDate}".FormatWith(user);
A third improved method p...
What is the difference between mutex and critical section?
... between the two of them. On my system for 1,000,000 uncontended acquires and releases, a mutex takes over one second. A critical section takes ~50 ms for 1,000,000 acquires.
Here's the test code, I ran this and got similar results if mutex is first or second, so we aren't seeing any other effect...
What is the difference between “text” and new String(“text”)?
...
new String("text");
explicitly creates a new and referentially distinct instance of a String object; String s = "text"; may reuse an instance from the string constant pool if one is available.
You very rarely would ever want to use the new String(anotherString) constru...
Convert SQLITE SQL dump file to POSTGRESQL
...n POSTGRESQL. I just updated my local database with a huge amount of data and need to transfer a specific table to the production database.
...
INSTALL_FAILED_NO_MATCHING_ABIS when install apk
I tried to install my app into Android L Preview Intel Atom Virtual Device, it failed with error:
24 Answers
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