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Abusing the algebra of algebraic data types - why does this work?
...gard that for the sake of simplicity.
A few initial points:
Note that "union" is probably not the best term for A+B here--that's specifically a disjoint union of the two types, because the two sides are distinguished even if their types are the same. For what it's worth, the more common term is ...
Merge and interleave two arrays in Ruby
...e a, you can write a | b and assign the result to a variable.
See the set union documentation for the Array class at http://www.ruby-doc.org/core/classes/Array.html#M000275.
This answer assumes that you don't want duplicate array elements. If you want to allow duplicate elements in your final arra...
What is the difference between 'protected' and 'protected internal'?
...
The "protected internal" access modifier is a union of both the "protected" and "internal" modifiers.
From MSDN, Access Modifiers (C# Programming Guide):
protected:
The type or member can be accessed only by code in the same class or
struct, or in a class that is...
In what areas might the use of F# be more appropriate than C#? [closed]
...a structures used to represent program code in F# are mostly discriminated unions (which are not supported in C# in any reasonable way) and this makes a huge difference for this kind of application (where you need to process tree structures, such as program code). Discriminated unions and pattern ma...
Why do you use typedef when declaring an enum in C++?
...amespaces but that is not technically correct. It has three:
Tags (enum, union, and struct)
Labels
(everything else)
typedef enum { } XYZ; declares an anonymous enumeration and imports it into the global namespace with the name XYZ.
typedef enum ABC { } XYZ; declares an enum named ABC in the ta...
List of Big-O for PHP functions
...:
isset/array_key_exists is much faster than in_array and array_search
+(union) is a bit faster than array_merge (and looks nicer). But it does work differently so keep that in mind.
shuffle is on the same Big-O tier as array_rand
array_pop/array_push is faster than array_shift/array_unshift due t...
How to perform OR condition in django queryset?
...st_name__startswith='D'
)
leads to
In [5]: str(queryset.query)
Out[5]: 'SELECT "auth_user"."id", "auth_user"."password", "auth_user"."last_login",
"auth_user"."is_superuser", "auth_user"."username", "auth_user"."first_name",
"auth_user"."last_name", "auth_user"."email", "auth_user"."is_staff",
"a...
How to randomly select rows in SQL?
...
SELECT TOP 5 Id, Name FROM customerNames
ORDER BY NEWID()
That said, everybody seems to come to this page for the more general answer to your question:
Selecting a random row in SQL
Select a random row with MySQL:
SELECT...
Get the last inserted row ID (with SQL statement) [duplicate]
...alue using:
INSERT INTO dbo.YourTable(columns....)
VALUES(..........)
SELECT SCOPE_IDENTITY()
This works as long as you haven't inserted another row - it just returns the last IDENTITY value handed out in this scope here.
There are at least two more options - @@IDENTITY and IDENT_CURRENT - r...
Formatting Numbers by padding with leading zeros in SQL Server
...
Change the number 6 to whatever your total length needs to be:
SELECT REPLICATE('0',6-LEN(EmployeeId)) + EmployeeId
If the column is an INT, you can use RTRIM to implicitly convert it to a VARCHAR
SELECT REPLICATE('0',6-LEN(RTRIM(EmployeeId))) + RTRIM(EmployeeId)
And the code to re...