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SQL how to make null values come last when sorting ascending
...d to compare the column in question to another date column. I use this for union seniority list. If employee has a Qualified date (which is nullable) , that date bubbles record to the top, otherwise use HireDate. Using ORDER BY ISNULL(QualifiedDate,'1-1-2099') , HireDate ,LastName, etc makes the Qu...
Condition within JOIN or WHERE
...left/right table rows extended by NULLs. FULL JOIN returns INNER JOIN rows UNION ALL unmatched left & right table rows extended by NULLs. Always know what INNER JOIN you want as part of an OUTER JOIN. A WHERE or ON that requires a possibly NULL-extended column to be not NULL after an OUTER JOIN ...
How to create enum like type in TypeScript?
...llo"
They are not very useful on their own but can be combined in a type union to create a powerful (and useful) abstraction e.g.:
type CardinalDirection =
"North"
| "East"
| "South"
| "West";
function move(distance: number, direction: CardinalDirection) {
// ...
}
move(1,"N...
Selecting data from two different servers in SQL Server
... 'Server=YOUR SERVER;Trusted_Connection=yes;','SELECT * FROM Table1') AS a
UNION
SELECT * FROM OPENROWSET('SQLNCLI', 'Server=ANOTHER SERVER;Trusted_Connection=yes;','SELECT * FROM Table1') AS a
share
|
...
What does immutable mean?
...ure but with mutable elements. This happens in some variations of undoable union-find IIRC. Immutability has big advantages, but sharing part or all of a data structure as an optimisation is perfectly possible with mutables. Even if you want apparent immutability for other references, you can always...
How to generate a range of numbers between two numbers?
...0
DECLARE @endnum INT=1050
;
WITH gen AS (
SELECT @startnum AS num
UNION ALL
SELECT num+1 FROM gen WHERE num+1<=@endnum
)
SELECT * FROM gen
option (maxrecursion 10000)
share
|
improv...
Is bool a native C type?
...goto
if
int
long
register
return
short
signed
static
struct
switch
typedef
union
unsigned
void
volatile
while
Here's an article discussing some other differences with C as used in the kernel and the standard: http://www.ibm.com/developerworks/linux/library/l-gcc-hacks/index.html
...
MySQL INNER JOIN select only one row from second table
...
@Fluffeh you have a very nice answer Part 1 - Joins and Unions. :) bookmarked!
– John Woo
Sep 21 '12 at 7:50
1
...
Is there common street addresses database design for all addresses of the world? [closed]
... lots of fields if you really want to be generic.
The UPU Universal Postal Union provides address data for lots of countries in a standard format. Note that the UPU format holds all addresses (down to the available field precision) for a whole country, it is therefore relational. If storing customer...
How to find the most recent file in a directory using .NET, and without looping?
...westFile(DirectoryInfo directory) {
return directory.GetFiles()
.Union(directory.GetDirectories().Select(d => GetNewestFile(d)))
.OrderByDescending(f => (f == null ? DateTime.MinValue : f.LastWriteTime))
.FirstOrDefault();
}
Just call it the fo...