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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...
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, &...
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...
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...
Parse date string and change format
...
convert string to datetime object
from datetime import datetime
s = "2016-03-26T09:25:55.000Z"
f = "%Y-%m-%dT%H:%M:%S.%fZ"
out = datetime.strptime(s, f)
print(out)
output:
2016-03-26 09:25:55
...
Programmatically obtain the Android API level of a device?
...ION.SDK_INT >= Build.VERSION_CODES.DONUT) {
}
To obtain user visible Android Version use:
Build.VERSION.RELEASE
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What are some uses of decltype(auto)?
... uses
You can also use decltype(auto) in other contexts, e.g. the draft Standard N3936 also states
7.1.6.4 auto specifier [dcl.spec.auto]
1 The auto and decltype(auto) type-specifiers designate a placeholder
type that will be replaced later, either by deduction from an
initializer or by ...
'0000-00-00 00:00:00' can not be represented as java.sql.Timestamp error
...ration:
jdbc:mysql://yourserver:3306/yourdatabase?zeroDateTimeBehavior=convertToNull
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How to check for file lock? [duplicate]
...
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...
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
1
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