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Javascript equivalent of Python's zip function
...date:
Here's a snazzier Ecmascript 6 version:
zip= rows=>rows[0].map((_,c)=>rows.map(row=>row[c]))
Illustration equiv. to Python{zip(*args)}:
> zip([['row0col0', 'row0col1', 'row0col2'],
['row1col0', 'row1col1', 'row1col2']]);
[["row0col0","row1col0"],
["row0col1","row1col1"...
What is an index in SQL?
...visited/scanned.
In SQL Server, a clustered index determines the physical order of data in a table. There can be only one clustered index per table (the clustered index IS the table). All other indexes on a table are termed non-clustered.
SQL Server Index Basics
SQL Server Indexes: The Basics
SQL...
add column to mysql table if it does not exist
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Note that INFORMATION_SCHEMA isn't supported in MySQL prior to 5.0. Nor are stored procedures supported prior to 5.0, so if you need to support MySQL 4.1, this solution isn't good.
One solution used by frameworks that use database migrations is...
Socket.IO - how do I get a list of connected sockets/clients?
...lients('room');
anymore. Instead you can use the following
var clients_in_the_room = io.sockets.adapter.rooms[roomId];
for (var clientId in clients_in_the_room ) {
console.log('client: %s', clientId); //Seeing is believing
var client_socket = io.sockets.connected[clientId];//Do whatever y...
How to check if a Constraint exists in Sql server?
... FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS where CONSTRAINT_NAME = 'UNIQUE_Order_ExternalReferenceId') BEGIN ALTER TABLE Order ADD CONSTRAINT UNIQUE_Order_ExternalReferenceId UNIQUE (ExternalReferenceId) END
– The Coder
Apr 15 '14 at 21:00
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Iterate a list as pair (current, next) in Python
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Since the_list[1:] actually creates a copy of the whole list (excluding its first element), and zip() creates a list of tuples immediately when called, in total three copies of your list are created. If your list is very large, you ...
How can I hash a password in Java?
...m recommended cost, used by default
*/
public static final int DEFAULT_COST = 16;
private static final String ALGORITHM = "PBKDF2WithHmacSHA1";
private static final int SIZE = 128;
private static final Pattern layout = Pattern.compile("\\$31\\$(\\d\\d?)\\$(.{43})");
private final Se...
How do you test that a Python function throws an exception?
...t ahold of the actual Exception object thrown:
import unittest
def broken_function():
raise Exception('This is broken')
class MyTestCase(unittest.TestCase):
def test(self):
with self.assertRaises(Exception) as context:
broken_function()
self.assertTrue('This i...
Pythonic way to print list items
...myList, sep='\n')
You can get the same behavior on Python 2.x using from __future__ import print_function, as noted by mgilson in comments.
With the print statement on Python 2.x you will need iteration of some kind, regarding your question about print(p) for p in myList not working, you can just...
How to do Base64 encoding in node.js?
...wered May 31 '11 at 2:46
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