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Simulate CREATE DATABASE IF NOT EXISTS for PostgreSQL?
...an work around it from within psql by executing the DDL statement conditionally:
SELECT 'CREATE DATABASE mydb'
WHERE NOT EXISTS (SELECT FROM pg_database WHERE datname = 'mydb')\gexec
The manual:
\gexec
Sends the current query buffer to the server, then treats each column of each row of the query's...
Delete an element from a dictionary
... use an an already constructed dict without a single item as **kwargs, some_function(**{k:v for k,v in some_dict.items() if k not 'some_key'})
– Cole
Nov 19 '17 at 21:14
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Force R not to use exponential notation (e.g. e+10)?
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This is a bit of a grey area. You need to recall that R will always invoke a print method, and these print methods listen to some options. Including 'scipen' -- a penalty for scientific display. From help(options):
‘scipen’: integer. A penalty to be applied wh...
Convert to binary and keep leading zeros in Python
...ction in Python. However, it always removes the leading zeros, which I actually need, such that the result is always 8-bit:
...
How to convert 2D float numpy array to 2D int numpy array?
...(int), np.array([-np.inf]).astype(int), and np.array([np.nan]).astype(int) all return the same thing. Why?
– BallpointBen
May 14 '18 at 20:47
1
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Redirecting from HTTP to HTTPS with PHP
...
Try something like this (should work for Apache and IIS):
if (empty($_SERVER['HTTPS']) || $_SERVER['HTTPS'] === "off") {
$location = 'https://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'];
header('HTTP/1.1 301 Moved Permanently');
header('Location: ' . $location);
exit;
}...
Showing the stack trace from a running Python application
... prompt for
interactive debugging."""
d={'_frame':frame} # Allow access to frame object.
d.update(frame.f_globals) # Unless shadowed by global
d.update(frame.f_locals)
i = code.InteractiveConsole(d)
message = "Signal received : entering python shell.\nTraceback:\n"...
Why is creating a Thread said to be expensive?
... there is a fair bit of work involved:
A large block of memory has to be allocated and initialized for the thread stack.
System calls need to be made to create / register the native thread with the host OS.
Descriptors need to be created, initialized and added to JVM-internal data structures.
It...
How to destroy an object?
... objects as soon as the page is served. So this should only be needed on really long loops and/or heavy intensive pages.
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LINQ Join with Multiple Conditions in On Clause
...
Here you go with:
from b in _dbContext.Burden
join bl in _dbContext.BurdenLookups on
new { Organization_Type = b.Organization_Type_ID, Cost_Type = b.Cost_Type_ID } equals
new { Organization_Type = bl.Organization_Type_ID, Cost_Type = bl.Cost_Type_ID }
...