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How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
...ou're on 9.5 and don't need to be backward-compatible you can stop reading now.
9.4 and older:
PostgreSQL doesn't have any built-in UPSERT (or MERGE) facility, and doing it efficiently in the face of concurrent use is very difficult.
This article discusses the problem in useful detail.
In general y...
Is there a HTML opposite to ?
...ag in HTML that will only display its content if JavaScript is enabled? I know <noscript> works the opposite way around, displaying its HTML content when JavaScript is turned off. But I would like to only display a form on a site if JavaScript is available, telling them why they can't use th...
How do you get a string from a MemoryStream?
If I am given a MemoryStream that I know has been populated with a String , how do I get a String back out?
11 Answers...
List of Rails Model Types
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I think this might be a more accurate link, now api.rubyonrails.org/classes/ActiveRecord/ConnectionAdapters/…
– Randy Burgess
Aug 12 '13 at 21:42
1...
Xcode 4: create IPA file instead of .xcarchive
...chive tango once again and go to the Organizer to select your new archive. Now, when clicking on the Share button, the .ipa option should be enabled.
I hope this helps.
share
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What is a “bundle” in an Android application
...in anystring with bundle key "myname"
b.putString("myname", anystring);
Now, create an Intent object
Intent in = new Intent(getApplicationContext(), secondActivity.class);
Pass bundle object b to the intent
in.putExtras(b);
and start second activity
startActivity(in);
In the second act...
Checkout subdirectories in Git?
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Sparse checkouts are now in Git 1.7.
Also see the question “Is it possible to do a sparse checkout without checking out the whole repository first?”.
Note that sparse checkouts still require you to download the whole repository, even though...
Uses for Optional
Having been using Java 8 now for 6+ months or so, I'm pretty happy with the new API changes. One area I'm still not confident in is when to use Optional . I seem to swing between wanting to use it everywhere something may be null , and nowhere at all.
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What does mysql error 1025 (HY000): Error on rename of './foo' (errorno: 150) mean?
..._id) REFERENCES
country (id) ON DELETE NO
ACTION ON UPDATE NO ACTION
Now simply issue an:
alter table region drop foreign key
region_ibfk_1;
And finally an:
alter table region drop column
country_id;
And you are good to go!
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File to byte[] in Java
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This now works on Android if targeting SDK version 26 and higher.
– JamesNWarner
Aug 9 '17 at 14:46
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