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How to drop a table if it exists?
... 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
IF OBJECT_ID('dbo.Scores', 'U') IS NOT NULL
DROP TABLE dbo.Scores;
Or, for a temporary table you can use
IF OBJECT_ID('...
How to make a variadic macro (variable number of arguments)
...eceding comma in case the variable-argument list is empty, eg. FOO("a") expands to printf("a"). This is an extension of gcc (and vc++, maybe), C99 requires at least one argument to be present in place of the ellipsis.
– jpalecek
Mar 26 '09 at 20:20
...
How to round the corners of a button
I have a rectangle image (jpg) and want to use it to fill the background of a button with rounded corner in xcode.
15 Answe...
Can't find how to use HttpContent
...
Says the content parameter needs to be IHttpContent and not StringContent. When I cast it to the interface it's happy, though.
– micahhoover
May 13 '15 at 1:39
...
Instantiate and Present a viewController in Swift
I started taking a look of the new Swift on Xcode 6 , and I tried some demo projects and tutorials. Now I am stuck at:
1...
Manipulate a url string by adding GET parameters
I want to add GET parameters to URLs that may and may not contain GET parameters without repeating ? or & .
15 Answe...
Add new row to dataframe, at specific row-index, not appended?
...1 2 3 4
41 4 9 14 19
5 5 10 15 20
(Note we index r differently).
And finally, benchmarks:
library(microbenchmark)
microbenchmark(
rbind(existingDF[1:r,],newrow,existingDF[-(1:r),]),
insertRow(existingDF,newrow,r)
)
Unit: microseconds
...
How to make an array of arrays in Java
...array references, initialized to the values array1, array2, array3, array4 and array5 - each of which is in itself a string array reference.
– Jon Skeet
Jan 24 '11 at 11:05
1
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Is it possible to delete an object's property in PHP?
...
unset($a->new_property);
This works for array elements, variables, and object attributes.
Example:
$a = new stdClass();
$a->new_property = 'foo';
var_export($a); // -> stdClass::__set_state(array('new_property' => 'foo'))
unset($a->new_property);
var_export($a); // -> st...
ASP.NET web.config: configSource vs. file attributes
...file in an ASP.NET-application some sections of config, like appSettings and connectionStrings , supports the attributes file and configSource .
...