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Calculate a Running Total in SQL Server
...QL Server implementation of the Over clause is somewhat limited.
Oracle (and ANSI-SQL) allow you to do things like:
SELECT somedate, somevalue,
SUM(somevalue) OVER(ORDER BY somedate
ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW)
AS RunningTotal
FROM Table
SQL Server gi...
Multi-line commands in GHCi
I am having problem in entering multi-line commands in ghci.
5 Answers
5
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Why does Math.floor return a double?
...seems inconsistent with the Math.Round functions, which do return int/long and handle the special cases in a different way.
– zod
May 11 '11 at 11:08
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What is the bit size of long on 64-bit Windows?
...o long ago, someone told me that long are not 64 bits on 64 bit machines and I should always use int . This did not make sense to me. I have seen docs (such as the one on Apple's official site) say that long are indeed 64 bits when compiling for a 64-bit CPU. I looked up what it was on 64-bit W...
Connecting overloaded signals and slots in Qt 5
... is that there are two signals with that name: QSpinBox::valueChanged(int) and QSpinBox::valueChanged(QString). From Qt 5.7, there are helper functions provided to select the desired overload, so you can write
connect(spinbox, qOverload<int>(&QSpinBox::valueChanged),
slider, &...
How to capitalize the first letter of a String in Java?
...makes sure the rest of the string is lower-case. That's what I needed when converting from ALL_CAPS enum names.
– Ellen Spertus
Nov 13 '15 at 17:40
add a comment
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What is the purpose of willSet and didSet in Swift?
...seems to be that sometimes, you need a property that has automatic storage and some behavior, for instance to notify other objects that the property just changed. When all you have is get/set, you need another field to hold the value. With willSet and didSet, you can take action when the value is mo...
Split data frame string column into multiple columns
...ing columns will have correct types and improve performance by adding type.convert and fixed arguments (since "_and_" isn't really a regex)
setDT(before)[, paste0("type", 1:2) := tstrsplit(type, "_and_", type.convert = TRUE, fixed = TRUE)]
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What is the Scala annotation to ensure a tail recursive function is optimized?
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From the "Tail calls, @tailrec and trampolines" blog post:
In Scala 2.8, you will also be able to use the new @tailrec annotation to get information about which methods are optimised.
This annotation lets you mark specific methods that you hope th...
How to check for file lock? [duplicate]
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No, unfortunately, and if you think about it, that information would be worthless anyway since the file could become locked the very next second (read: short timespan).
Why specifically do you need to know if the file is locked anyway? Knowing...