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How to concatenate string variables in Bash
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While no special chars, nor spaces are used, double quotes, quotes and curly brackets are useless: var=myscript;var=$var.sh;echo $var would have same effects (This work under bash, dash, busybox and others).
– F. Hauri...
When to use EntityManager.find() vs EntityManager.getReference() with JPA
... }
}
If i call find method, JPA provider, behind the scenes, will call
SELECT NAME, AGE FROM PERSON WHERE PERSON_ID = ?
UPDATE PERSON SET AGE = ? WHERE PERSON_ID = ?
If i call getReference method, JPA provider, behind the scenes, will call
UPDATE PERSON SET AGE = ? WHERE PERSON_ID = ?
And ...
Remove the last character in a string in T-SQL?
... ELSE LEFT(@String, LEN(@String) - 1)
END
) END
SELECT @String
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Count(*) vs Count(1) - SQL Server
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The optimizer recognizes it for what it is: trivial.
The same as EXISTS (SELECT * ... or EXISTS (SELECT 1 ...
Example:
SELECT COUNT(1) FROM dbo.tab800krows
SELECT COUNT(1),FKID FROM dbo.tab800krows GROUP BY FKID
SELECT COUNT(*) FROM dbo.tab800krows
SELECT COUNT(*),FKID FROM dbo.tab800krows GROU...
Better techniques for trimming leading zeros in SQL Server?
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Why don't you just cast the value to INTEGER and then back to VARCHAR?
SELECT CAST(CAST('000000000' AS INTEGER) AS VARCHAR)
--------
0
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How to create an installer for a .net Windows Service using Visual Studio
...out dragging stuff from the toolbox.
Then right click on the gray area and select add installer. This will add an installer project file to your project.
Then you will have 2 components on the design view of the ProjectInstaller.cs (serviceProcessInstaller1 and serviceInstaller1). You should then se...
How do I use the CONCAT function in SQL Server 2008 R2?
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You can use SELECT {fn concat ('foo', 'bar')}; in previous versions. Only accepts 2 parameters though.
– Martin Smith
May 11 '12 at 11:22
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How to get current timestamp in milliseconds since 1970 just the way Java gets
...e 767990892 which is round 8 days after the epoch ;-).
int main(int argc, char* argv[])
{
struct timeval tp;
gettimeofday(&tp, NULL);
long long mslong = (long long) tp.tv_sec * 1000L + tp.tv_usec / 1000; //get current timestamp in milliseconds
std::cout << mslong << ...
Invalid postback or callback argument. Event validation is enabled using '
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I had an experience with DataGrid. One of it's columns was "Select" button. When I was clicking "Select" button of any row I had received this error message:
"Invalid postback or callback argument. Event validation is enabled using in configuration or
<%@ Page EnableEve...
LINQ to SQL - Left Outer Join with multiple join conditions
...g.Where(f => f.otherid == 17).DefaultIfEmpty()
where p.companyid == 100
select f.value
Or you could use a subquery:
from p in context.Periods
join f in context.Facts on p.id equals f.periodid into fg
from fgi in (from f in fg
where f.otherid == 17
select f).DefaultIfE...
