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MySQL: Set user variable from result of query
...ame} and this '{variable_name}', we can replace it with our variable name.
Now, how to assign a value in a variable in mysql. For this we have many ways to do that
Using keyword 'SET'.
Example :-
mysql > SET @a = 1;
Without using keyword 'SET' and using ':='.
Example:-
mysql > @a:=1;
B...
What is the most efficient Java Collections library? [closed]
...
Hey, Jon, Google Java Collections is now Guava. You might want to update your post for future references :)
– Artur Czajka
Oct 25 '11 at 18:24
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Extract date (yyyy/mm/dd) from a timestamp in PostgreSQL
...estamp;
timestamp
---------------------
2010-01-01 12:00:00
Now we'll cast it to a date:
wconrad=# select '2010-01-01 12:00:00'::timestamp::date;
date
------------
2010-01-01
On the other hand you can use date_trunc function. The difference between them is that the latter ...
Storing JSON in database vs. having a new column for each key
...a types and the support in PostgreSQL was in its infancy. Since 5.7, MySQL now supports a JSON data type (in a binary storage format), and PostgreSQL JSONB has matured significantly. Both products provide performant JSON types that can store arbitrary documents, including support for indexing specif...
Why does the JVM still not support tail-call optimization?
...ementation and MLVM has listed the feature as "proto 80%" for some time now.
4 Answers
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How to use npm with node.exe?
...ually create the directory/folder C:\Users\kevitt\AppData\Roaming\npm just now before I could install my first package.
– Kenny Evitt
Aug 14 '14 at 14:33
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Push git commits & tags simultaneously
... push" to push relevant annotated tags when pushing branches out.
You can now try, when pushing new commits:
git push --follow-tags
That won't push all the local tags though, only the one referenced by commits which are pushed with the git push.
Git 2.4.1+ (Q2 2015) will introduce the option push....
Why doesn't Dijkstra's algorithm work for negative weight edges?
...int on positive numbers - the above assumption is not true.
Since we do "know" each vertex which was "closed" is minimal - we can safely do the relaxation step - without "looking back". If we do need to "look back" - Bellman-Ford offers a recursive-like (DP) solution of doing so.
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When should you use constexpr capability in C++11?
...t b ) { return a * b; }
const int meaningOfLife = MeaningOfLife( 6, 7 );
Now you have something that can be evaluated down to a constant while maintaining good readability and allowing slightly more complex processing than just setting a constant to a number.
It basically provides a good aid to ma...
Reopen last closed tab in Visual Studio
...studio.com/… which includes the Power Commands. It‘s not working right now as I‘m writing and the bug report is here github.com/Microsoft/VS-PPT/issues/208
– bugybunny
Nov 8 '18 at 7:10
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