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Convert Rows to columns using 'Pivot' in SQL Server
...) which allows doesn't require that you explicitly name the different "FOR ____ IN (...)"
– The Red Pea
Aug 13 '15 at 22:03
1
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Multiple Inheritance in PHP
...
This is both a question and a solution....
What about the magical _call(),_get(), __set() methods? I have not yet tested this solution but what if you make a multiInherit class. A protected variable in a child class could contain an array of classes to inherit. The constructor in the multi-...
.NET / C# - Convert char[] to string
...oin("", chars);
//we get "a string"
// or for fun:
string s = string.Join("_", chars);
//we get "a_ _s_t_r_i_n_g"
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Throw an error in a MySQL trigger
...e SIGNAL syntax to throw an exception:
signal sqlstate '45000' set message_text = 'My Error Message';
State 45000 is a generic state representing "unhandled user-defined exception".
Here is a more complete example of the approach:
delimiter //
use test//
create table trigger_test
(
id int...
MySQL Removing Some Foreign keys
...You can use this to find foreign key constraints: SELECT * FROM information_schema.table_constraints WHERE constraint_schema = '<your db name>' AND constraint_type = 'FOREIGN KEY'
– Gayan Dasanayake
Aug 26 '17 at 2:48
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Invert “if” statement to reduce nesting
... clearer. For example:
double getPayAmount() {
double result;
if (_isDead) result = deadAmount();
else {
if (_isSeparated) result = separatedAmount();
else {
if (_isRetired) result = retiredAmount();
else result = normalPayAmount();
};
...
Reference - What does this error mean in PHP?
..., which resulted in headers to be already sent to the client.
This is an E_WARNING and it will not stop the script.
A typical example would be a template file like this:
<html>
<?php session_start(); ?>
<head><title>My Page</title>
</html>
...
The ses...
Getting a random value from a JavaScript array
...u've already got underscore or lodash included in your project you can use _.sample.
// will return one item randomly from the array
_.sample(['January', 'February', 'March']);
If you need to get more than one item randomly, you can pass that as a second argument in underscore:
// will return tw...
Best algorithm for detecting cycles in a directed graph [closed]
...e following Wikipedia article:
http://en.wikipedia.org/wiki/Topological_sorting
has the pseudo-code for one algorithm, and a brief description of another from Tarjan. Both have O(|V| + |E|) time complexity.
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No mapping found for field in order to sort on in ElasticSearch
...
After digging more, I found the solution as given below. ignore_unmapped should be explicitly set to true in the sort clause.
"sort" : [
{ "rating": {"order" : "desc" , "ignore_unmapped" : true} },
{ "price": {"order" : "asc" , "missing" : "_last" , "ignore_unmapped" : tru...