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What is the difference between the | and || or operators?
...dition2 | condition3)
This will check conditions 2 and 3, even if 1 is already true. As your conditions can be quite expensive functions, you can get a good performance boost by using them.
There is one big caveat, NullReferences or similar problems. For example:
if(class != null && clas...
On duplicate key ignore? [duplicate]
...nd You have to take into account potential performance hit. Instead of one read and potential one write You get read, write (delete row), write (insert row) and write(update index), so 1x read and 3x write (at best, if only one index is updated)..
– matt
Oct 18...
Javascript date.getYear() returns 111 in 2011? [duplicate]
...nally (but it has since been updated to use getFullYear()). I would never read w3schools for anything :)
– JK.
Jul 24 '12 at 21:33
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How to substring in jquery
... sleep. I've cleaned things up here a little. Meanwhile, somebody needs to read this
– BoltClock♦
Jan 24 '13 at 7:21
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Can Json.NET serialize / deserialize to / from a stream?
...no need to vote down, this is correct on older versions).
Use the JsonTextReader class with a StreamReader or use the JsonSerializer overload that takes a StreamReader directly:
var serializer = new JsonSerializer();
serializer.Deserialize(streamReader);
...
There is already an open DataReader associated with this Command which must be closed first
...
This worked for me. If you want to read more about Enabling Multiple Active Result Sets (MARS) see msdn.microsoft.com/en-us/library/h32h3abf(v=vs.100).aspx. Consider reading up on Disadvantages of MARS too stackoverflow.com/questions/374444/…
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What is the correct SQL type to store a .Net Timespan with values > 24:00:00?
...tetime or datetimeoffset, that stores the result of first date + timespan. Reading from the db is a matter of TimeSpan x = SecondDate - FirstDate. Using this option will protect you for other non .NET data access libraries access the same data but not understanding TimeSpans; in case you have such a...
How to explain callbacks in plain english? How are they different from calling one function from ano
...of integer 4 in "a" parameter, the callback_funct will return 6 as result. Read this callbackhell.com best source I found.
– Dung
Nov 1 '17 at 10:03
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How to learn R as a programming language [closed]
... might want to look at this article by John Cook. Also make sure that you read "The R Inferno".
There are many good resources on the R homepage, but in particular, read "An Introduction to R" and "The R Language Definition".
Some very closely related stackoverflow questions:
books-for-learning-...
jquery change class name
...r dom object. How do I grab the td's id and change its class? - maybe i am reading it wrong, maybe he means use the td's id to change the class...
– Bob Fincheimer
Aug 10 '10 at 19:59
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