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MySQL IF NOT NULL, then display 1, else display 0
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SELECT c.name, IF(a.addressid IS NULL,0,1) AS addressexists
FROM customers c
LEFT JOIN addresses a ON c.customerid = a.customerid
WHERE customerid = 123
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How to shuffle a std::vector?
...zer.h"
#include <iostream>
using namespace std;
int main (int argc, char* argv[]) {
vector<int> v;
v.push_back(1);v.push_back(2);v.push_back(3);v.push_back(4);v.push_back(5);
v.push_back(6);v.push_back(7);v.push_back(8);v.push_back(9);v.push_back(10);
Randomizer::get_in...
CASCADE DELETE just once
...you want to cascade.
DELETE FROM some_child_table WHERE some_fk_field IN (SELECT some_id FROM some_Table);
DELETE FROM some_table;
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How to generate a random int in C?
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If you need secure random characters or integers:
As addressed in how to safely generate random numbers in various programming languages, you'll want to do one of the following:
Use libsodium's randombytes API
Re-implement what you need from libsod...
Declaration suffix for decimal type
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Whilst not a suffix, we can also declare a character with char c = 'a' using apostrophes around the character.
– Kevin Hogg
Aug 26 '15 at 8:05
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HTML for the Pause symbol in audio and video control
...y default) in order to instruct the parser how to transform the bytes into characters correctly. <meta charset="utf-8"/> should be used immediately after <head> in a HTML file, and make sure the correct HTTP headers Content-Type: text/html; charset=utf-8 are set.
Examples:
HTML
&...
Create PostgreSQL ROLE (user) if it doesn't exist
...r fashion to what you had in mind:
DO
$do$
BEGIN
IF NOT EXISTS (
SELECT FROM pg_catalog.pg_roles -- SELECT list can be empty for this
WHERE rolname = 'my_user') THEN
CREATE ROLE my_user LOGIN PASSWORD 'my_password';
END IF;
END
$do$;
(Building on @a_horse_with_no_name's...
Is there a way to select sibling nodes?
For some performance reasons, I am trying to find a way to select only sibling nodes of the selected node.
13 Answers
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How does the String class override the + operator?
...sion (§15.9):
If T is boolean, then use new Boolean(x).
If T is char, then use new Character(x).
If T is byte, short, or int, then use new Integer(x).
If T is long, then use new Long(x).
If T is float, then use new Float(x).
If T is double, then use new Double(x).
This ref...
How to open existing project in Eclipse
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Project > Import > General > Select Root Directory > (do NOT select copy projects into workspace). This is useful if you use Eclipse outside scope of Java project as well, such as Ruby projects or C projects.
– JohnMerlino
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