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Can existing virtualenv be upgraded gracefully?
I have a virtualenv created for Python 2.5 and want to "upgrade" it to Python 2.6.
5 Answers
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Iteration over std::vector: unsigned vs signed index variable
... use difference_type? sizeof is defined to return size_t :) i don't understand you. if i were to subtract pointers from each other, difference_type would be the right choice.
– Johannes Schaub - litb
Jan 4 '09 at 9:38
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How to Define Callbacks in Android?
...
In many cases, you have an interface and pass along an object that implements it. Dialogs for example have the OnClickListener.
Just as a random example:
// The callback interface
interface MyCallback {
void callbackCall();
}
// The class that takes the c...
How to convert linq results to HashSet or HashedSet
...f T explicitly:
var query = from i in Enumerable.Range(0, 10)
select new { i, j = i + 1 };
var resultSet = query.ToHashSet();
You can't do that with an explicit call to the HashSet<T> constructor. We're relying on type inference for generic methods to do it for us.
Now you coul...
Give all the permissions to a user on a DB
...%', ( -- use instead of EXECUTE to see generated commands
EXECUTE (
SELECT string_agg(format('GRANT USAGE ON SCHEMA %I TO my_user', nspname), '; ')
FROM pg_namespace
WHERE nspname <> 'information_schema' -- exclude information schema and ...
AND nspname NOT LIKE 'pg\_%' ...
How can I clear the SQL Server query cache?
...et DBID from one database name first
DECLARE @intDBID INT;
SET @intDBID = (SELECT [dbid]
FROM master.dbo.sysdatabases
WHERE name = N'AdventureWorks2014');
DBCC FLUSHPROCINDB (@intDBID);
7. Clear plan cache for the current database
USE AdventureWorks2014;
GO
-- New...
How to find what code is run by a button or element in Chrome using Developer Tools
... tab, and on the right find Event
Listener Breakpoints:
Expand Mouse and select click
Now click the element (execution should pause), and you are now debugging the code. You can go through all code pressing F11 (which is Step in). Or go back a few jumps in the stack. There can be a ton of jumps
...
PreparedStatement with list of parameters in a IN clause [duplicate]
... possibleValue.size(); i++ ) {
builder.append("?,");
}
String stmt = "select * from test where field in ("
+ builder.deleteCharAt( builder.length() -1 ).toString() + ")";
PreparedStatement pstmt = ...
And then happily set the params
int index = 1;
for( Object o : possibleVal...
What's the difference between VARCHAR and CHAR?
...CHAR(10),
Street VARCHAR(10));
Insert into temp
values('Pune','Oxford');
select length(city), length(street) from temp;
Output will be
length(City) Length(street)
10 6
Conclusion: To use storage space efficiently must use VARCHAR Instead CHAR if variable length is ...
Choosing a file in Python with simple Dialog
...= askopenfilename() # show an "Open" dialog box and return the path to the selected file
print(filename)
Done!
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