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How do I add a library project to Android Studio?
..., go to Project Structure -> under Modules just hit the plus button and select Import Existing Project and import actionbarsherlock. Then synchronise your Gradle files.
If you face the error
Error: The SDK Build Tools revision (xx.x.x) is too low. Minimum
required is yy.y.y
just open the...
Aggregate / summarize multiple variables per group (e.g. sum, mean)
...-date), sum)
# summarising a specific set of non-grouping variables using select_helpers
# see ?select_helpers for more options
df2 <- df1 %>% group_by(year, month) %>% summarise_at(vars(starts_with('x')), sum)
df2 <- df1 %>% group_by(year, month) %>% summarise_at(vars(matches('.*...
How can I define a composite primary key in SQL?
...for the table and neither value can be NULL. If you do a query like this:
SELECT * FROM voting WHERE QuestionID = 7
it will use the primary key's index. If however you do this:
SELECT * FROM voting WHERE MemberID = 7
it won't because to use a composite index requires using all the keys from th...
How can I convert tabs to spaces in every file of a directory?
...s on each line;
-t 4 means that each tab will be converted to 4 whitespace chars (8 by default).
sponge is from the moreutils package, and avoids clearing the input file.
Finally, you can use gexpand on OSX, after installing coreutils with Homebrew (brew install coreutils).
...
HTTPS with Visual Studio's built-in ASP.NET Development Server
...
Select the project-file in the Solution Explorer: for example: "WebApplication1".
With pressing ALT+ENTER you enter the project-properties.
Select "DEBUG" on the left side.
Here you can select "Enable SSL".
Then you can...
Update multiple columns in SQL
...
The Update table1 set (a,b,c) = (select x,y,x) syntax is an example of the use of
row-value constructors, Oracle supports this, MSSQL does not. (Connect item)
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Extract elements of list at odd positions
...he first element (at position 0, because the indexes are 0-based) would be selected. In this case the second element will be selected.
Because the second element is omitted, the default is being used (the end of the list). So the list is being iterated from the second element to the end.
We also p...
How to select records from last 24 hours using SQL?
...
SELECT *
FROM table_name
WHERE table_name.the_date > DATE_SUB(CURDATE(), INTERVAL 1 DAY)
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How can I Remove .DS_Store files from a Git repository?
...prefer xargs because I don't have to worry about escaping a lot of special characters.
– benzado
Sep 21 '08 at 7:13
8
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How to parse a query string into a NameValueCollection in .NET
...=');
if (parts.Length > 0)
{
string key = parts[0].Trim(new char[] { '?', ' ' });
string val = parts[1].Trim();
queryParameters.Add(key, val);
}
}
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