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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 bind inverse boolean properties in WPF?
...I need to go with a solution that "I" will remember, which I will use over and over. I also feel that the less wordy something is the better, and creating an inverse property is very explicit, making it easy for me to remember, as well as future dev's ( I Hope, I Hope ), to be able to quickly see ...
How many database indexes is too many?
...nds on the operations that occur on the table.
If there's lots of SELECTs and very few changes, index all you like.... these will (potentially) speed the SELECT statements up.
If the table is heavily hit by UPDATEs, INSERTs + DELETEs ... these will be very slow with lots of indexes since they all ...
Error: CUICatalog: Invalid asset name supplied: (null), or invalid scale factor : 2.000000
...on on 32-bit iPhone, or $x2 == nil on 64-bit iPhone.
Run your application and see where debugger will stop.
P.S. Keep in mind this also happens if image name is empty string. You can check this by adding [(NSString*)$x2 length] == 0 to the condition.
...
Fastest method of screen capturing on Windows
...to use GDI, but I'm curious whether there are other ways to go about this, and, if there are, which incurs the least overhead? Speed is a priority.
...
What does “not run” mean in R help pages?
...isible on help pages, but will
be run both by the package checking tools, and the
'example()' function. This was previously 'testonly', and
that form is still accepted.
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What is an invariant?
... of a program state that is always true..." - @jacob baskin - well written and thanks for this.
– twknab
May 31 '19 at 23:37
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How to find index of list item in Swift?
...
As swift is in some regards more functional than object-oriented (and Arrays are structs, not objects), use the function "find" to operate on the array, which returns an optional value, so be prepared to handle a nil value:
let arr:Array = ["a","b","c"]
find(arr, "c")! // 2
fi...
Can I disable a CSS :hover effect via JavaScript?
...ernative workaround though. If you don’t mind mucking about in your HTML and CSS a little bit, it saves you having to reset every CSS property manually via JavaScript.
HTML
<body class="nojQuery">
CSS
/* Limit the hover styles in your CSS so that they only apply when the nojQuery
class...
Difference between Key, Primary Key, Unique Key and Index in MySQL
When should I use KEY , PRIMARY KEY , UNIQUE KEY and INDEX ?
8 Answers
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