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PostgreSQL Crosstab Query
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This does not work for me, for postgresql. I get the error ERROR: 42803: aggregate function calls may not be nested
– Audrey
Nov 12 '14 at 12:05
1
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Why can't C++ be parsed with a LR(1) parser?
... but gave it
up for hand-coded parsing, I think because they wanted
better error diagnostics.
There's another approach, though, which is nice and clean
and parses C and C++ just fine without any symbol table
hackery: GLR parsers.
These are full context free parsers (having effectively infinite
look...
Principles for Modeling CouchDB Documents
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Active
Oldest
Votes
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What's the use of Jade or Handlebars when writing AngularJs apps
...hing like:
.control-group(
ng-form
name='emailGroup'
ng-class='{"ng-error": emailGroup.$invalid}'
)
label.control-label Email
.controls
input(
type='email'
ng-model='user.email'
required
placeholder='you@example.com'
focus-on='focusEmail'
)
… whic...
Django migration strategy for renaming a model and relationship fields
...ions.RenameField('YetAnotherModel', 'foo', 'bar')
]
You may get some errors if you don't update the names where it's imported e.g. admin.py and even older migration files (!).
Update: As ceasaro mentions, newer versions of Django are usually able to detect and ask if a model is renamed. So tr...
python design patterns [closed]
...nd the primitive Null value.
This object just eats the lack of attribute error, and you can avoid checking for their existence.
It's nothing more than
class Null(object):
def __init__(self, *args, **kwargs):
"Ignore parameters."
return None
def __call__(self, *args, **k...
How to verify if a file exists in a batch file?
...hat the /c /d /h /e /i /y means:
/C Continues copying even if errors occur.
/D:m-d-y Copies files changed on or after the specified date.
If no date is given, copies only those files whose
source time is newer than the destination time.
/H ...
How to add leading zeros for for-loop in shell? [duplicate]
...
Use the following syntax:
$ for i in {01..05}; do echo "$i"; done
01
02
03
04
05
Disclaimer: Leading zeros only work in >=bash-4.
If you want to use printf, nothing prevents you from putting its result in a variable for further use:
$ foo=$(printf "%02d" 5)
$ ech...
Android adb “Unable to open sync connection!”
...files" issue. I manually tried to install the app when getting the "sync" error above and that's when I got the "too many open files" clue. one brute workaround, based on some old posts, seems to be to restart the phone, and one google engineer suggested doing it twice, the second time before it g...
How to calculate the running time of my program? [duplicate]
...s in the main method, calendar will be defined two times -> compilation error
– krtek
Mar 5 '11 at 13:35
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