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What is the fastest or most elegant way to compute a set difference using Javascript arrays?
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Why JavaScript sets don't have union/intersect/difference built in is beyond me...
– SwiftsNamesake
Nov 27 '16 at 4:50
6
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Difference between left join and right join in SQL Server [duplicate]
...i
Null Null Kathmandu
Full Join
Note : It is same as union operation, it will return all selected values from both tables.
Syntax:
SELECT column_name(s) FROM table1 FULL OUTER JOIN table2 ON table1.column_name = table2.column_name;
Apply it in your samp[le table:
SELECT...
What is the difference between HashSet and List?
...ady existing in Set
Can perform mathematical set operations against a Set: Union/Intersection/IsSubsetOf etc.
HashSet doesn't implement IList only ICollection
You cannot use indices with a HashSet, only enumerators.
The main reason to use a HashSet would be if you are interested in performing Set ...
Where is C not a subset of C++? [closed]
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In C++, if you declare a struct, union, or enum, its name is immediately accessible without any qualifiers:
struct foo { ... };
foo x; // declare variable
In C, this won't work, because types thus declared live in their own distinct namespaces. Thus, you ...
Hidden Features of Java
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Joint union in type parameter variance:
public class Baz<T extends Foo & Bar> {}
For example, if you wanted to take a parameter that's both Comparable and a Collection:
public static <A, B extends Collection<A&g...
Remove Identity from a column in a table
...IX_Original_Value ON Original (Value);
INSERT INTO Original
SELECT 'abcd'
UNION ALL
SELECT 'defg';
You can do the following:
--create new table with no IDENTITY
CREATE TABLE Original2
(
Id INT PRIMARY KEY
, Value NVARCHAR(300)
);
CREATE NONCLUSTERED INDEX IX_Original_Value2 ON Original2 (Valu...
Enforcing the type of the indexed members of a Typescript object?
... a similar syntax to enforce that an object has a key for every entry in a union type:
type DayOfTheWeek = "sunday" | "monday" | "tuesday" | "wednesday" | "thursday" | "friday" | "saturday";
type ChoresMap = { [day in DayOfTheWeek]: string };
const chores: ChoresMap = { // ERROR! Property 'saturd...
How to remove leading and trailing whitespace in a MySQL field?
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DROP TABLE IF EXISTS tbl;
CREATE TABLE tbl
AS
SELECT 'Afghanistan' AS txt
UNION ALL
SELECT ' AF' AS txt
UNION ALL
SELECT ' Cayman Islands ' AS txt
UNION ALL
SELECT CONCAT(CONCAT(CONCAT('\t \t ', CHAR(12)), ' \r\n\t British Virgin Islands \t \t ', CHAR(12)), ' \r\n') AS txt;
SELECT format_re...
Difference between Select Unique and Select Distinct
...re trying to do. You can eliminate duplicates by choosing the appropriate union statement parameters.
the below query by itself will only provide distinct values
select col from table1
union
select col from table2
if you did want duplicates you would have to do
select col from table1
union ...
XPath OR operator for different nodes
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@user569008: | is the union set operator.
– user357812
Mar 18 '11 at 19:35
1
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