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How to add an auto-incrementing primary key to an existing table, in PostgreSQL?
...of PostgreSQL
In old versions of PostgreSQL (prior to 8.x?) you had to do all the dirty work. The following sequence of commands should do the trick:
ALTER TABLE test1 ADD COLUMN id INTEGER;
CREATE SEQUENCE test_id_seq OWNED BY test1.id;
ALTER TABLE test ALTER COLUMN id SET DEFAULT nextval('...
How do I get a background location update every n minutes in my iOS application?
...d with UIApplication:beginBackgroundTaskWithExpirationHandler:
When n is smaller than UIApplication:backgroundTimeRemaining it will work just fine. When n is larger, the location manager should be enabled (and disabled) again before there is no time remaining to avoid the background task being kille...
Android phone orientation overview including compass
...
Roll is a function of gravity, a 90 degree roll puts all of gravity into the x register.
Pitch is the same, a 90 degree pitch up puts all of the component of gravity into the y register.
Yaw / Heading / azimuth has no effect on gravity, it is ALWAYS at right angles to gravity...
Proper indentation for Python multiline strings
... and long if statements, though not mentioned for multiline strings. Personally this is one place I refuse to follow PEP8 (and use 4-space indenting instead), as I strongly dislike hanging indents, which for me obscure the proper structure of the program.
– bobince
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Android Spinner: Get the selected item change event
... answered Nov 11 '09 at 10:50
znqznq
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Is there a python equivalent of Ruby's 'rvm'?
Q: Do we have anything functionally equivalent in Python to the Ruby version manager 'rvm' ?
6 Answers
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Find Oracle JDBC driver in Maven repository
...(note I pulled the groupId, artifactId and version from the POM):
mvn install:install-file -DgroupId=com.oracle -DartifactId=ojdbc14 \
-Dversion=10.2.0.3.0 -Dpackaging=jar -Dfile=ojdbc.jar -DgeneratePom=true
The last parameter for generating a POM will save you from pom.xml warnings
If your...
Controlling the screenshot in the iOS 7 multitasking switcher
...ome information regarding the new multitasking switcher in iOS 7 and especially the screenshot that the OS takes when the app is going into hibernation.
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Save PL/pgSQL output from PostgreSQL to a CSV file
...e to your local PC. It also needs to be run as a Postgres "superuser" (normally called "root") because Postgres can't stop it doing nasty things with that machine's local filesystem.
That doesn't actually mean you have to be connected as a superuser (automating that would be a security risk of a di...
How does TransactionScope roll back transactions?
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Essentially TransactionScope doesn't track your Adapter's, what it does is it tracks database connections. When you open a DB connection the connections will looks if there is an ambient transaction (Transaction Scope) and if so enl...