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How to declare a variable in MySQL?
... refer to a variable that has not been
initialized, it has a value of NULL and a type of string.
SELECT @var_any_var_name
You can initialize a variable using SET or SELECT statement:
SET @start = 1, @finish = 10;
or
SELECT @start := 1, @finish := 10;
SELECT * FROM places WHERE place BET...
Why java.lang.Object is not abstract? [duplicate]
...e argued that some of the methods would benefit from this. Take hashCode() and equals() for instance, there would probably have been a lot less frustration around the complexities of these two if they had both been made abstract. This would require developers to figure out how they should be impleme...
Java Programming - Where should SQL statements be stored? [closed]
Where should an JDBC-compliant application store its SQL statements and why?
15 Answers
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Is file append atomic in UNIX?
...n NFS.
But assuming you write to a log file you opened in 'O_APPEND' mode and keep your lines (including newline) under 'PIPE_BUF' bytes long, you should be able to have multiple writers to a log file without any corruption issues. Any interrupts will arrive before or after the write, not in the m...
Views vs Components in Ember.js
I am learning ember.js, and I am trying to understand the difference between a view and a component. I see both as a way of making reusable components.
...
Find and replace with sed in directory and sub directories
I run this command to find and replace all occurrences of 'apple' with 'orange' in all files in root of my site:
7 Answers
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Is object empty? [duplicate]
...y = Object.prototype.hasOwnProperty;
function isEmpty(obj) {
// null and undefined are "empty"
if (obj == null) return true;
// Assume if it has a length property with a non-zero value
// that that property is correct.
if (obj.length > 0) return false;
if (obj.length...
Can't start site in IIS (use by another process)
...
Check using netstat -aon or netstat -aon | findstr 0.0:80 in a command prompt to see which Process Id is LISTENING to port :80 and then watch for that Process Id (PID) in Task Manager with view->select columns-> process id checked. End that process, restart IIS and you are done. (Note:...
Slowing speed of Viewpager controller in android
Is there any way to slow the scroll speed with the viewpager adaptor in android?
10 Answers
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Geometric Mean: is there a built-in?
...
Here is a vectorized, zero- and NA-tolerant function for calculating geometric mean in R. The verbose mean calculation involving length(x) is necessary for the cases where x contains non-positive values.
gm_mean = function(x, na.rm=TRUE){
exp(sum(log...