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Difference between Key, Primary Key, Unique Key and Index in MySQL
When should I use KEY , PRIMARY KEY , UNIQUE KEY and INDEX ?
8 Answers
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Using group by on multiple columns
I understand the point of GROUP BY x .
2 Answers
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Why should casting be avoided? [closed]
...as possible since I am under the impression that it's poor coding practice and may incur a performance penalty.
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git pull from master into the development branch
I have a branch called dmgr2 (development) and I want to pull from the master branch (live site) and incorporate all the changes into my development branch. is there a better way to do this?
here is what I had planned on doing, after committing changes:
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Why does 1==1==1 return true, “1”==“1”==“1” return true, and “a...
I tested the above code in Chrome's console and for some reason, a() returns true, b() returns true, and c() returns false.
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How can I reliably get an object's address when operator& is overloaded?
...(); is declared, then func is a reference to a function taking no argument and returning no result. This reference to a function can be trivially converted into a pointer to function -- from @Konstantin: According to 13.3.3.2 both T & and T * are indistinguishable for functions. The 1st one is a...
What is difference between width, innerWidth and outerWidth, height, innerHeight and outerHeight in
... to see what is the difference, but they display me same results for width and height.
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Which timestamp type should I choose in a PostgreSQL database?
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First off, PostgreSQL’s time handling and arithmetic is fantastic and Option 3 is fine in the general case. It is, however, an incomplete view of time and timezones and can be supplemented:
Store the name of a user’s time zone as a user preference (e....
Why is rbindlist “better” than rbind?
I am going through documentation of data.table and also noticed from some of the conversations over here on SO that rbindlist is supposed to be better than rbind .
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How to get whole and decimal part of a number?
Given, say, 1.25 - how do I get "1" and ."25" parts of this number?
16 Answers
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