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Finding duplicate values in MySQL
I have a table with a varchar column, and I would like to find all the records that have duplicate values in this column. What is the best query I can use to find the duplicates?
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Is it possible to ping a server from Javascript?
...quires that I check to see if remote servers are online or not. When I run it from the command line, my page load goes up to a full 60s (for 8 entries, it will scale linearly with more).
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SQL select only rows with max value on a column [duplicate]
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At first glance...
All you need is a GROUP BY clause with the MAX aggregate function:
SELECT id, MAX(rev)
FROM YourTable
GROUP BY id
It's never that simple, is it?
I just noticed you need the content column as well.
This is a very common question in SQL: find the whole data...
Programmatically open Maps app in iOS 6
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Here's the official Apple way:
// Check for iOS 6
Class mapItemClass = [MKMapItem class];
if (mapItemClass && [mapItemClass respondsToSelector:@selector(openMapsWithItems:launchOptions:)])
{
// Create an MKMapItem to pass to the Maps app
CLLocationCoordinate2D coordi...
What are the security risks of setting Access-Control-Allow-Origin?
...calls.
Now I can't help but feel that I'm putting my environment to security risks.
Please help me if I'm doing it wrong.
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What is your preferred php deployment strategy? [closed]
...heir preferred strategy for PHP deployment. I'd love to automate things a bit so that once changes are committed they can be quickly migrated to a development or production server.
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What's the difference between 'git merge' and 'git rebase'?
What's the difference between git merge and git rebase ?
7 Answers
7
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How do I disable form fields using CSS?
Is it possible to disable form fields using CSS? I of course know about the attribute disabled, but is it possible to specify this in a CSS rule? Something like -
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MySQL vs PostgreSQL for Web Applications [closed]
...Django) and would like to know whether MySQL or PostgreSQL would be more suitable when deploying for production.
10 Answer...
Generate UML Class Diagram from Java Project [closed]
...ML that will show an overview of how my classes are related to each other? It doesn't need to decompile from JAR file because I have the sources. I know there are quite a few out there but most of those can only generate individual class. I hope there is a tool that can generate class diagram that s...