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Apply function to all elements of collection through LINQ [duplicate]
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@BKSpurgeon: Select is a projection: 1) it's lazily evaluated; just calling it won't do anything. 2) Select produces a result - ForEach doesn't.
– Jon Skeet
Mar 20 '17 at 9:24
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How do the PHP equality (== double equals) and identity (=== triple equals) comparison operators dif
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@Pim ...continued: Look at it this way: Casting to a BOOL, any value only has to fall on one of two sides, true or false. That's easy to cast. All other values though have, for all practical purposes, virtually unlimited combinations. Is "five" == 5? array(0) == 0?...
How to create a generic array in Java?
...generic collection in Effective Java; Item 26. No type errors, no need to cast the array repeatedly. However this triggers a warning because it is potentially dangerous, and should be used with caution. As detailed in the comments, this Object[] is now masquerading as our E[] type, and can cause ...
SQL Server dynamic PIVOT query?
... @cols AS NVARCHAR(MAX),
@query AS NVARCHAR(MAX);
SET @cols = STUFF((SELECT distinct ',' + QUOTENAME(c.category)
FROM temp c
FOR XML PATH(''), TYPE
).value('.', 'NVARCHAR(MAX)')
,1,1,'')
set @query = 'SELECT date, ' + @cols + ' from
(...
How to return multiple objects from a Java method?
...pressWarnings("unchecked")
public static <P, Q> Pair<P, Q> cast(Pair<?, ?> pair, Class<P> pClass, Class<Q> qClass) {
if (pair.isInstance(pClass, qClass)) {
return (Pair<P, Q>) pair;
}
throw new ClassCastException();
}...
How to do a regular expression replace in MySQL?
...ositions and perform substring substitution and extraction, respectively.
SELECT REGEXP_REPLACE('Stackoverflow','[A-Zf]','-',1,0,'c');
-- Output:
-tackover-low
DBFiddle Demo
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How do I convert from int to Long in Java?
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Note that there is a difference between a cast to long and a cast to Long. If you cast to long (a primitive value) then it should be automatically boxed to a Long (the reference type that wraps it).
You could alternatively use new to create an instance of Long, init...
How to check if field is null or empty in MySQL?
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Either use
SELECT IF(field1 IS NULL or field1 = '', 'empty', field1) as field1
from tablename
or
SELECT case when field1 IS NULL or field1 = ''
then 'empty'
else field1
end as field1
from tablename
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How to strip all non-alphabetic characters from string in SQL Server?
...ex(@KeepValues, @Temp), 1, '')
Return @Temp
End
Call it like this:
Select dbo.RemoveNonAlphaCharacters('abc1234def5678ghi90jkl')
Once you understand the code, you should see that it is relatively simple to change it to remove other characters, too. You could even make this dynamic enough ...
TSQL - How to use GO inside of a BEGIN .. END block?
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@gbn @mellamokb: I meant statements like SELECT * <newline> FROM whatever. If I execute every line with its own EXEC statement, that will break. Or are you suggesting I break at every GO statement?
– BlueRaja - Danny Pflughoeft
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