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How do I convert an interval into a number of hours with postgres?
...
Probably the easiest way is:
SELECT EXTRACT(epoch FROM my_interval)/3600
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Function to Calculate Median in SQL Server
... in all cases. It also requires SQL 2012 or later.
DECLARE @c BIGINT = (SELECT COUNT(*) FROM dbo.EvenRows);
SELECT AVG(1.0 * val)
FROM (
SELECT val FROM dbo.EvenRows
ORDER BY val
OFFSET (@c - 1) / 2 ROWS
FETCH NEXT 1 + (1 - @c % 2) ROWS ONLY
) AS x;
Of course, just because o...
Get first day of week in SQL Server
...in that there should be some sensible logic built in to round up or down:
SELECT DATEDIFF(YEAR, '2010-01-01', '2011-12-31');
SELECT DATEDIFF(YEAR, '2010-12-31', '2011-01-01');
To answer how to get a Sunday:
If you want a Sunday, then pick a base date that's not a Monday but rather a Sunday. For ...
When should you use 'friend' in C++?
...te, the C++ FAQ mentions that friend enhances encapsulation. friend grants selective access to members, just like protected does. Any fine-grained control is better than granting public access. Other languages define selective access mechanisms too, consider C#'s internal. Most negative criticism ar...
Properly removing an Integer from a List
... is equal to Integer(1) will be removed. In both cases, the Java compiler selects the closest matching overload.
Yes, there is potential for confusion (and bugs) here, but it is a fairly uncommon use-case.
When the two List.remove methods were defined in Java 1.2, the overloads were not ambiguous...
Sleep Command in T-SQL?
...(@hours * 60) * 60)) - (@mins * 60)
IF @hours > 23
BEGIN
select @hours = 23
select @mins = 59
select @secs = 59
-- 'maximum wait time is 23 hours, 59 minutes and 59 seconds.'
END
declare @sql nvarchar(24) = 'WAITFOR DELAY '+char(39)+cast(@hours as nvarchar(2))...
Schema for a multilanguage database
...t PostGreSQL with hstore), you can't pass a parameter language, and say:
SELECT ['DESCRIPTION_' + @in_language] FROM T_Products
So you have to do this:
SELECT
Product_UID
,
CASE @in_language
WHEN 'DE' THEN DESCRIPTION_DE
WHEN 'SP' THEN DESCRIPTION_SP
EL...
ReadOnlyCollection or IEnumerable for exposing member collections?
...y of other options for wrapping trivially - the nice thing about Skip over Select/Where is that there's no delegate to execute pointlessly for each iteration.)
If you're not using .NET 3.5 you can write a very simple wrapper to do the same thing:
public static IEnumerable<T> Wrapper<T>...
Entity Framework and SQL Server View
...mn as a primary key, use NULLIF.
An easy way to apply this is to wrap the select statement of your view in another select.
Example:
SELECT
ISNULL(MyPrimaryID,-999) MyPrimaryID,
NULLIF(AnotherProperty,'') AnotherProperty
FROM ( ... ) AS temp
...
Deserialize JSON into C# dynamic object?
...st<object>(arrayList.Cast<IDictionary<string, object>>().Select(x => new DynamicJsonObject(x)))
: new List<object>(arrayList.Cast<object>());
}
return result;
}
}
#endregion
}
You can use it like this:
...