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Insert into … values ( SELECT … FROM … )
...SERT from another table I did the following in SQLite3:
INSERT INTO column_1 ( val_1, val_from_other_table )
VALUES('val_1', (SELECT val_2 FROM table_2 WHERE val_2 = something))
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What is the size of an enum in C?
... having only that, the following is valid i think: enum { LAST = INT_MAX, LAST1, LAST2 }; so LAST2 is not representable in int, but there wasn't an expression defining it.
– Johannes Schaub - litb
Dec 14 '08 at 1:33
...
Get names of all keys in the collection
...You could do this with MapReduce:
mr = db.runCommand({
"mapreduce" : "my_collection",
"map" : function() {
for (var key in this) { emit(key, null); }
},
"reduce" : function(key, stuff) { return null; },
"out": "my_collection" + "_keys"
})
Then run distinct on the resulting collecti...
I want to delete all bin and obj folders to force all projects to rebuild everything
... you can use this:
Get-ChildItem .\ -include bin,obj -Recurse | foreach ($_) { remove-item $_.fullname -Force -Recurse }
as seen in Robert H's answer below - just make sure you give him credit for the powershell answer rather than me if you choose to up-vote anything :)
It would of course be wis...
Download the Android SDK components for offline install
...available
Fetching https://dl-ssl.google.com/android/repository/addons_list-2.xml
Fetched Add-ons List successfully
Fetching URL: https://dl-ssl.google.com/android/repository/repository-7.xml
Validate XML: https://dl-ssl.google.com/android/repository/repository-7.xml
Parse XML: https...
Download file from web in Python 3
....request
...
# Download the file from `url` and save it locally under `file_name`:
urllib.request.urlretrieve(url, file_name)
import urllib.request
...
# Download the file from `url`, save it in a temporary directory and get the
# path to it (e.g. '/tmp/tmpb48zma.txt') in the `file_name` variable:...
“is” operator behaves unexpectedly with integers
...tively rare. Here's an example (will work in Python 2 and 3) e.g.
SENTINEL_SINGLETON = object() # this will only be created one time.
def foo(keyword_argument=None):
if keyword_argument is None:
print('no argument given to foo')
bar()
bar(keyword_argument)
bar('baz')
def b...
How to model type-safe enum types?
... val Mon, Tue, Wed, Thu, Fri, Sat, Sun = Value
}
import WeekDay._
def isWorkingDay(d: WeekDay) = ! (d == Sat || d == Sun)
WeekDay.values filter isWorkingDay foreach println
}
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Ways to implement data versioning in MongoDB
...nt contain a dictionary of time-stamped diffs. Something like this:
{
_id : "id of address book record",
changes : {
1234567 : { "city" : "Omaha", "state" : "Nebraska" },
1234568 : { "city" : "Kansas City", "state" : "Missouri" }
}
}
To make...
Xcode/Simulator: How to run older iOS version?
...
To add previous iOS simulator to Xcode 4.2, you need old xcode_3.2.6_and_ios_sdk_4.3.dmg (or similar version) installer file and do as following:
Mount the xcode_3.2.6_and_ios_sdk_4.3.dmg file
Open mounting disk image and choose menu: Go->Go to Folder...
Type /Volumes/Xcode and iOS...