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When do I need to use Begin / End Blocks and the Go keyword in SQL Server?
..., and IF statements, etc, where you need more then one step...
IF EXISTS (SELECT * FROM my_table WHERE id = @id)
BEGIN
INSERT INTO Log SELECT @id, 'deleted'
DELETE my_table WHERE id = @id
END
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How to pass values between Fragments
... I tried step 5, That i'm calling listactivity from fragment and after selecting item from that activity, i want to come back in fragment with selected file name. But its not working, its giving me Nullpointer Exception at onCreateView. Any solution on this please? This is my question stackoverf...
Django ManyToMany filter()
...d it.
the above code will end up generating SQL that looks something like:
SELECT * FROM users WHERE id IN (SELECT user_id FROM userzones WHERE zone_id IN (1,2,3))
which is nice because it doesn't have any intermediate joins that could cause duplicate users to be returned
...
Is there a way to rename an Xcode 4 scheme?
... hit "Manage Schemes". Once you do so, you'll have a window like this:
Select the scheme you want to change, and hit Return.
Now the scheme name will be editable, and you can change it to your hearts desire. Then hit Return again to save it.
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How to reshape data from long to wide format
...mes(df) <- unique(dat1$name)
df
sqldf package:
library(sqldf)
sqldf('SELECT name,
MAX(CASE WHEN numbers = 1 THEN value ELSE NULL END) x1,
MAX(CASE WHEN numbers = 2 THEN value ELSE NULL END) x2,
MAX(CASE WHEN numbers = 3 THEN value ELSE NULL END) x3,
MAX(CASE WHEN numbe...
How to use JNDI DataSource provided by Tomcat in Spring?
..."7200000"
testOnBorrow="true"
validationQuery="select 1"
/>
</GlobalNamingResources>
And reference the JNDI resource from Tomcat's web context.xml like this:
<ResourceLink name="jdbc/DatabaseName"
global="jdbc/DatabaseName"
type="javax...
Get a list of distinct values in List
...
Notes.Select(x => x.Author).Distinct();
This will return a sequence (IEnumerable<string>) of Author values -- one per unique value.
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How to get the max of two values in MySQL?
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Use GREATEST()
E.g.:
SELECT GREATEST(2,1);
Note: Whenever if any single value contains null at that time this function always returns null (Thanks to user @sanghavi7)
s...
input type=file show only button
...
<input type="file" id="selectedFile" style="display: none;" />
<input type="button" value="Browse..." onclick="document.getElementById('selectedFile').click();" />
This will surely work i have used it in my projects.I hope this helps :)
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Undo VS 'Exclude from project'?
...alled "Show All Files". To see this button, make sure that your project is selected in the solution explorer.
Show All Files
When this option is active, the file should be there, just grayed out. Right click it, and select "Include In Project".
Include In Project
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