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How to request a random row in SQL?
...andom row from a database table. It goes through methods for doing this in MySQL, PostgreSQL, Microsoft SQL Server, IBM DB2 and Oracle (the following is copied from that link):
Select a random row with MySQL:
SELECT column FROM table
ORDER BY RAND()
LIMIT 1
Select a random row with PostgreSQL:
...
What's the best way to store co-ordinates (longitude/latitude, from Google Maps) in SQL Server?
...
I don't know the answer for SQL Server but...
In MySQL save it as FLOAT( 10, 6 )
This is the official recommendation from the Google developer documentation.
CREATE TABLE `coords` (
`lat` FLOAT( 10, 6 ) NOT NULL ,
`lng` FLOAT( 10, 6 ) NOT NULL ,
) ENGINE = MYISAM ;
...
Applications are expected to have a root view controller at the end of application launch
... see the layout from a storyboard make sure you got rid of the code in you root delegate function "application didFinishLaunchingWithOptions..." that's pointed at in main.m and only have "return YES;" in it.
– Olivier de Jonge
Jun 26 '14 at 11:01
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How does the vim “write with sudo” trick work?
...ve probably seen the command that allows you to write on a file that needs root permission, even when you forgot to open vim with sudo:
...
Create a CSV File for a user in PHP
I have data in a MySQL database. I am sending the user a URL to get their data out as a CSV file.
19 Answers
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How do you configure Django for simple development and deployment?
...
development, but on a live server something more robust is
often needed ( MySQL / PostgreSQL , for example).
Invariably, there are other changes to make to the Django
settings as well: different logging locations / intensities,
media paths, etc.
...
How to check if smtp is working from commandline (Linux) [closed]
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[root@piwik-dev tmp]# mail -v root@localhost
Subject: Test
Hello world
Cc: <Ctrl+D>
root@localhost... Connecting to [127.0.0.1] via relay...
220 piwik-dev.example.com ESMTP Sendmail 8.13.8/8.13.8; Thu, 23 Aug 2012 10:4...
Breadth First Vs Depth First
...
Both kinds of traversal can be achieved with the pseudocode:
Store the root node in Container
While (there are nodes in Container)
N = Get the "next" node from Container
Store all the children of N in Container
Do some work on N
The difference between the two traversal orders lies in ...
Can I try/catch a warning?
...t a lot of time debugging a problem in a system where someone had written @mysql_query( '...' ) and the problem was that mysql support was not loaded into PHP and it threw a silent fatal error. It will be safe for those things that are part of the PHP core but please use it with care.
bob@mypc:~$ p...
Access nested dictionary items via a list of keys?
...uce # forward compatibility for Python 3
import operator
def get_by_path(root, items):
"""Access a nested object in root by item sequence."""
return reduce(operator.getitem, items, root)
def set_by_path(root, items, value):
"""Set a value in a nested object in root by item sequence.""...