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Facebook database design?
...O_INCREMENT=2 DEFAULT CHARSET=utf8;
Friends of Friends Query:
(
select friend_id
from friends
where user_id = 1
) union (
select distinct ff.friend_id
from
friends f
join friends ff on ff.user_id = f.friend_id
where f.use...
Convert data.frame column format from character to factor
...yr::mutate_if() to convert all character columns or dplyr::mutate_at() for select named character columns to factors:
library(dplyr)
# all character columns to factor:
df <- mutate_if(df, is.character, as.factor)
# select character columns 'char1', 'char2', etc. to factor:
df <- mutate_at(d...
How do you test private methods with NUnit?
...
This should be the selected answer, as it is the only one which actually answers the question.
– bavaza
Dec 10 '13 at 16:04
...
Appropriate datatype for holding percent values?
...to 1.00. For instance:
declare @discount numeric(9,9)
, @quantity int
select @discount = 0.999999999
, @quantity = 10000
select convert(money, @discount * @quantity)
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Unable to type in Visual Studio
...hange the "Source Control Plug-In" to "None" (Source Control -> Plug-in Selection)
Restart Visual Studio
Repeat steps 1-3, except re-enable AnkhSVN in step 2
I was able to edit files again after this.
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Postgres: “ERROR: cached plan must not change result type”
...ng this error.
My application opened a database connection and prepared a SELECT statement for execution.
Meanwhile, another script was modifying the database table, changing the data type of one of the columns being returned in the above SELECT statement.
I resolved this by restarting the applic...
Handling a Menu Item Click Event - Android
...inflate(R.menu.game_menu, menu);
return true;
}
simple code for menu selected
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle item selection
switch (item.getItemId()) {
case R.id.new_game:
newGame();
return true;
case R.id.help:
...
LINQ .Any VS .Exists - What's the difference?
... Enumerable.Repeat("ABCDEFGHIJKLMNOPQRSTUVWXYZ", 13)
.Select(s =>
{
var cryptoResult = new byte[4];
new RNGCryptoServiceProvider().GetBytes(cryptoResult);
return s[new Random(BitConverter.ToInt32(cryp...
Enabling auto layout in iOS 6 while remaining backwards compatible with iOS 5
...tolayout can be enabled or disabled on each .storyboard or .xib file. Just select the particular file and modify the "Use Autolayout" property using the File inspector in Xcode:
Using autolayout enabled interface files with the deployment target set to an iOS version prior to 6.0 results in compi...
How do I specify “close existing connections” in sql script
...RE @isStatAsyncOn bit
DECLARE @jobId int
DECLARE @sqlString nvarchar(500)
SELECT @dbId = database_id,
@isStatAsyncOn = is_auto_update_stats_async_on
FROM sys.databases
WHERE name = 'db_name'
IF @isStatAsyncOn = 1
BEGIN
ALTER DATABASE [db_name] SET AUTO_UPDATE_STATISTICS_ASYNC OFF
...