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How to drop a table if it exists?
...
Is it correct to do the following?
IF EXISTS(SELECT *
FROM dbo.Scores)
DROP TABLE dbo.Scores
No. That will drop the table only if it contains any rows (and will raise an error if the table does not exist).
Instead, for a permanent table you can use
I...
Is there a way to automatically generate getters and setters in Eclipse?
...nu (i.e. right click) in the source code window of the desired class. Then select the Source submenu; from that menu selecting Generate Getters and Setters... will cause a wizard window to appear.
Source -> Generate Getters and Setters...
Select the variables you wish to create getters and sett...
Change name of iPhone app in Xcode 4
...veryone:
1.In the project contents pane at left, click the Folder icon.
2.Select the top-level blue line representing the project.
3.If you don't have the Inspector pane (right pane) open, click the button to enable it. This is the third button in the "View" toolbar towards the upper right corner...
What is the best way to filter a Java Collection?
...without writing loops or inner classes:
List<Person> beerDrinkers = select(persons, having(on(Person.class).getAge(),
greaterThan(16)));
Can you imagine something more readable?
Disclaimer: I am a contributor on lambdaj
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How to do SELECT COUNT(*) GROUP BY and ORDER BY in Django?
...lvaro has answered the Django's direct equivalent for GROUP BY statement:
SELECT actor, COUNT(*) AS total
FROM Transaction
GROUP BY actor
is through the use of values() and annotate() methods as follows:
Transaction.objects.values('actor').annotate(total=Count('actor')).order_by()
However ...
Get Selected index of UITableView
I want to have selected index for UITableView .
I have written following code:
5 Answers
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jQuery set radio button
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Your selector looks for the descendant of a input:radio[name=cols] element that has the id of newcol (well the value of that variable).
Try this instead (since you're selecting by ID anyway):
$('#' + newcol).prop('checked',true)...
Get selected option text with JavaScript
...
Try options
function myNewFunction(sel) {
alert(sel.options[sel.selectedIndex].text);
}
<select id="box1" onChange="myNewFunction(this);">
<option value="98">dog</option>
<option value="7122">cat</option>
<option value="142">bird</option&g...
Selecting multiple columns in a pandas dataframe
...7 44
R3 47 30 84
R4 41 62 1
R5 5 58 0
...
Same works for selecting rows based on labels. Get the rows 'R6' to 'R10' from those columns:
df.loc['R6':'R10', 'C':'E']
Out:
C D E
R6 51 27 31
R7 83 19 18
R8 11 67 65
R9 78 27 29
R10 7 16 94
.loc also ac...
Making macOS Installer Packages which are Developer ID ready
...gbuild
persisting obsolescence
Known Issues and Workarounds
Destination Select Pane
The user is presented with the destination select option with only a single choice - "Install for all users of this computer". The option appears visually selected, but the user needs to click on it in order to p...