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How can I create a unique constraint on my column (SQL Server 2008 R2)?
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Or set column as unique from the SQL Query window:
alter table location_key drop constraint pinky;
alter table your_table add constraint pinky unique(yourcolumn);
Changes take effect immediately:
Command(s) completed successfully.
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Rename Files and Directories (Add Prefix)
...ll work for filenames with spaces in them:
for f in * ; do mv -- "$f" "PRE_$f" ; done
("--" is needed to succeed with files that begin with dashes, whose names would otherwise be interpreted as switches for the mv command)
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Why does sys.exit() not exit when called inside a thread in Python?
...from the thread?
Apart from the method Deestan described you can call os._exit (notice the underscore). Before using it make sure that you understand that it does no cleanups (like calling __del__ or similar).
share
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Python Unicode Encode Error
..., "utf-8", errors="ignore")
else:
# Assume the value object has proper __unicode__() method
value = unicode(value)
If you would like to read more about why:
http://docs.plone.org/manage/troubleshooting/unicode.html#id1
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Share Large, Read-Only Numpy Array Between Multiprocessing Processes
...n
from multiprocessing import Process
import sharedmem
import numpy
def do_work(data, start):
data[start] = 0;
def split_work(num):
n = 20
width = n/num
shared = sharedmem.empty(n)
shared[:] = numpy.random.rand(1, n)[0]
print "values are %s" % shared
processes = [Proc...
PHP equivalent of .NET/Java's toString()
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@MarkAmery He gave an answer that implicitly calls the __toString() "Magic Method", but didn't mention that at all. The user asked for an answer that was like the Java toString() method, and in PHP, that's the __toString() function.
– Supuhstar
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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"...
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...
Add a new column to existing table in a migration
...lashing with existing models
for Laravel 3:
php artisan migrate:make add_paid_to_users
for Laravel 5+:
php artisan make:migration add_paid_to_users_table --table=users
You then need to use the Schema::table() method (as you're accessing an existing table, not creating a new one). And you ca...
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 ...