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MySQL Conditional Insert
... AND item = 456)
In this, dual is a table with one row only (found originally in Oracle, now in mysql too). The logic is that the SELECT statement generates a single row of data with the required values, but only when the values are not already found.
Alternatively, look at the MERGE statement.
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How to find out if a Python object is a string?
...r with unicode.
However, you may not need to do explicit type checking at all. "Duck typing" may fit your needs. See http://docs.python.org/glossary.html#term-duck-typing.
See also What’s the canonical way to check for type in python?
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How can I remove duplicate rows?
.../02/18/not-exists-vs-not-in Out of the 3 I think NOT EXISTS performs best. All three will generate a plan with a self join though that can be avoided.
– Martin Smith
Jan 14 '11 at 9:17
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Is there a case insensitive jQuery :contains selector?
...ive version of the :contains jQuery selector or should I do the work manually by looping over all elements and comparing their .text() to my string?
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NSOperation vs Grand Central Dispatch
...ed first, but as of 10.5 and iOS 2, NSOperationQueue and friends are internally implemented using GCD.
In general, you should use the highest level of abstraction that suits your needs. This means that you should usually use NSOperationQueue instead of GCD, unless you need to do something that NSOp...
Build fat static library (device + simulator) using Xcode and SDK 4+
It appears that we can - theoretically - build a single static library that includes both simulator and iPhone and iPad.
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Does .NET provide an easy way convert bytes to KB, MB, GB, etc.?
...}
And here's the original implementation I suggested, which may be marginally slower, but a bit easier to follow:
static readonly string[] SizeSuffixes =
{ "bytes", "KB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB" };
static string SizeSuffix(Int64 value, int decimalPlaces = 1)
{...
Does PHP have threading?
I found this PECL package called threads , but there is not a release yet. And nothing is coming up on the PHP website.
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Convert RGB to RGBA over white
... rgba(0, 62, 123, .404).
I have verified in Photoshop that the colors actually match perfectly.
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Filtering DataGridView without changing datasource
...rce as DataTable).DefaultView.RowFilter = rowFilter;
The square brackets allow for spaces in the column name.
Additionally, if you want to include multiple values in your filter, you can add the following line for each additional value:
rowFilter += string.Format(" OR [{0}] = '{1}'", columnName,...