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What is a columnar database?
...receive less resources/interest than work on "General Purpose", "Tried and Tested", tabular approach.
Tentatively, the Entity-Attribute-Value (EAV) data model, may be an alternative storage strategy which you may want to consider. Although distinct from the "pure" Columnar DB model, EAV shares sev...
How to prune local tracking branches that do not exist on remote anymore
...rios, as well, such as if I create three separate branches off origin/A to test three different approaches to something, and then origin/A goes away. Now I have three branches, which obviously can't all match name-wise, but they were created from origin/A, and so a literal interpretation of the OPs ...
iPhone UIButton - image position
...label results misplaced, probably because the UIImageView is not inserted (Tested on iOS6.0). You should consider editing frames only if imageView.image is not nil.
– Scakko
Apr 17 '13 at 15:19
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Random record in ActiveRecord
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This is fastest solution
– Sergio Belevskij
Jan 12 '17 at 14:25
1
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Django - How to rename a model field using South?
...I had a column with a uniqueness constraint, renamed it using this method, tested that the uniqueness constraint still existed and got an error but the name of the constraint itself was still using the old column name. Perhaps an explicit db.delete_unique and db.create_unique would have done it but ...
Fastest check if row exists in PostgreSQL
...ou can use "PERFORM" in a function just like this:
PERFORM 1 FROM skytf.test_2 WHERE id=i LIMIT 1;
IF FOUND THEN
RAISE NOTICE ' found record id=%', i;
ELSE
RAISE NOTICE ' not found record id=%', i;
END IF;
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Getting Spring Application Context
...at approach can fail if you call getBean from code that runs during a Unit test because the Spring context will not be set up before you ask for it. Its a race condition I just slammed into today after 2 years of successfully using this approach.
– HDave
Aug 2...
How to remove unreferenced blobs from my git repo
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I tested with git version 2.17 and stashed commits will not be removed by the above commands. Are you sure you didn't run any additional commands?
– Mikko Rantalainen
May 6 at 17:37
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How can I hash a password in Java?
...port javax.crypto.spec.PBEKeySpec;
/**
* Hash passwords for storage, and test passwords against password tokens.
*
* Instances of this class can be used concurrently by multiple threads.
*
* @author erickson
* @see <a href="http://stackoverflow.com/a/2861125/3474">StackOverflow</a...
How to get distinct values for non-key column fields in Laravel?
... I have a table "messages" (used for a chat), and I want to get the latest message that the authenticated user has received from each conversation. Using groupBy I can get just one message, but I get the first, and I need the last message. Seems that orderBy doesn't work.
–...