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MySQL “WITH” clause
...l#recursive_queries
Informix 14.10 and later:
https://www.ibm.com/support/knowledgecenter/SSGU8G_14.1.0/com.ibm.sqls.doc/ids_sqs_with.htm
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What is std::move(), and when should it be used?
...
template <class T>
swap(T& a, T& b) {
T tmp(a); // we now have two copies of a
a = b; // we now have two copies of b (+ discarded a copy of a)
b = tmp; // we now have two copies of tmp (+ discarded a copy of b)
}
using move allows you to swap the resources inste...
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Check if object value exists within a Javascript array of objects and if not add a new object to arr
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18 Answers
18
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Is it possible to GROUP BY multiple columns using MySQL?
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– user2360831
Jun 15 '19 at 6:17
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Can I get CONST's defined on a PHP class?
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You can use Reflection for this. Note that if you are doing this a lot you may want to looking at caching the result.
<?php
class Profile {
const LABEL_FIRST_NAME = "First Name";
const LABEL_LAST_NAME = "Last Name";
const LABEL_COMPANY_NAME = "Company"...
How do you write a migration to rename an ActiveRecord model and its table in Rails?
...y.
Edit:
In Rails 3.1 & 4, ActiveRecord::Migration::CommandRecorder knows how to reverse rename_table migrations, so you can do this:
class RenameOldTableToNewTable < ActiveRecord::Migration
def change
rename_table :old_table_name, :new_table_name
end
end
(You still have to go t...