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Count number of records returned by group by

...his to DISTINCT COUNT() OVER(), and the query performance improved dramatically. – Joe Aldrich Sep 20 '17 at 13:33  |  show 3 more comments ...
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How to change the name of a Django app?

...e changed the name of an app in Django by renaming its folder, imports and all its references (templates/indexes). But now I get this error when I try to run python manage.py runserver ...
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Append an object to a list in R in amortized constant time, O(1)?

...irthday. Some kind readers keep repeating any shortcomings with it, so by all means also see some of the comments below. One suggestion for list types: newlist <- list(oldlist, list(someobj)) In general, R types can make it hard to have one and just one idiom for all types and uses. ...
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Correct owner/group/permissions for Apache 2 site files/folders under Mac OS X?

...go-rwx DIR (nobody other than owner can access content) chmod go+x DIR (to allow "users" including _www to "enter" the dir) sudo chgrp -R _www ~/my/web/root (all web content is now group _www) chmod -R go-rwx ~/my/web/root (nobody other than owner can access web content) chmod -R g+rx ~/my/web/root...
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Multiple Models in a single django ModelForm?

... But how? Usually a FormView only has a single form_class assigned to it. – erikbwork Oct 7 '16 at 17:42 ...
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How to quit scala 2.11.0 REPL?

... I ran into the same issue on upgrade, just use colon q. :q Additionally, exit was deprecated in 2.10.x with sys.exit suggested instead, so this works as well: sys.exit As a side note, I think they did this so you can distinguish between exiting the scala console in sbt and exiting sbt its...
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How to convert ASCII code (0-255) to its corresponding character?

...mes, to be safe) on my machine gives an average time of 153.07 nanoseconds vs. 862.39 nanoseconds. However, in any interesting application, there will be far more important things to optimize. The added value of the safe, deterministic handling and ease of expanding outside the [0,255] range should ...
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How to check a string for specific characters?

...r other characters. ... or pattern = re.compile(r'\d\$,') if pattern.findall(s): print('Found') else print('Not found') ... or chars = set('0123456789$,') if any((c in chars) for c in s): print('Found') else: print('Not Found') [Edit: added the '$' in s answers] ...
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Bootstrap 3 - Why is row class is wider than its container?

... In all grid systems, there are gutters between each column. Bootstrap's system sets a 15px padding on both the left and the right of each column to create this gutter. The issue is that the first column should not have half a g...
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How to print a query string with parameter values when using Hibernate

...he the following categories: org.hibernate.SQL   - set to debug to log all SQL DML statements as they are executed org.hibernate.type - set to trace to log all JDBC parameters So a log4j configuration could look like: # logs the SQL statements log4j.logger.org.hibernate.SQL=debug # Logs the...