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Create unique constraint with null columns
...0000-0000-0000-0000-000000000000'), RecipeId);
You'd just need to pick a UUID for the COALESCE that will never occur in "real life". You'd probably never see a zero UUID in real life but you could add a CHECK constraint if you are paranoid (and since they really are out to get you...):
alter tabl...
How do I associate a Vagrant project directory with an existing VirtualBox VM?
...e ".vagrant" file in the same directory as your "Vagrantfile" to track the UUID of your VM. This file will not exist if a VM does not exist. The format of the file is JSON. It looks like this if a single VM exists:
{
"active":{
"default":"02f8b71c-75c6-4f33-a161-0f46a0665ab6"
}
}
defa...
JAX-RS — How to return JSON and HTTP status code together?
...
Here's an example:
@GET
@Path("retrieve/{uuid}")
public Response retrieveSomething(@PathParam("uuid") String uuid) {
if(uuid == null || uuid.trim().length() == 0) {
return Response.serverError().entity("UUID cannot be blank").build();
}
Entity en...
How do I initialize a byte array in Java?
I have to store some constant values (UUIDs) in byte array form in java, and I'm wondering what the best way to initialize those static arrays would be. This is how I'm currently doing it, but I feel like there must be a better way.
...
Is iterating ConcurrentHashMap values thread safe?
...tHashMap:
import java.util.Map;
import java.util.Random;
import java.util.UUID;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
public class ConcurrentMapIteration
{
private final Map<String, String> map = n...
How to get POSTed JSON in Flask?
..., request, jsonify
app = Flask(__name__)
@app.route('/api/add_message/<uuid>', methods=['GET', 'POST'])
def add_message(uuid):
content = request.json
print content['mytext']
return jsonify({"uuid":uuid})
if __name__ == '__main__':
app.run(host= '0.0.0.0',debug=True)
...
What is the iBeacon Bluetooth Profile
...
For an iBeacon with ProximityUUID E2C56DB5-DFFB-48D2-B060-D0F5A71096E0, major 0, minor 0, and calibrated Tx Power of -59 RSSI, the transmitted BLE advertisement packet looks like this:
d6 be 89 8e 40 24 05 a2 17 6e 3d 71 02 01 1a 1a ff 4c 00 02 15 e2 c5...
Generate random string/characters in JavaScript
...ters of hex.
Option 2
If you have to do this client-side, perhaps try the uuid module -
var uuid = require("uuid");
var id = uuid.v4();
// "110ec58a-a0f2-4ac4-8393-c866d813b8d1"
Option 3
If you have to do this client-side and you don't have to support old browsers, you can do it without dependen...
Generating a random & unique 8 character string using MySQL
...ting an 8-character long pseudo-random string in pure (My)SQL:
SELECT LEFT(UUID(), 8);
You can try the following (pseudo-code):
DO
SELECT LEFT(UUID(), 8) INTO @plate;
INSERT INTO plates (@plate);
WHILE there_is_a_unique_constraint_violation
-- @plate is your newly assigned plate number
S...
How to suppress GCC warnings from library headers?
...gma GCC diagnostic ignored "-Wunused-but-set-variable"
#include <boost/uuid/uuid.hpp>
#include <boost/uuid/uuid_generators.hpp>
#include <boost/uuid/uuid_io.hpp>
#include <boost/lexical_cast.hpp>
// turn the warnings back on
#pragma GCC diagnostic pop
...