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MongoDB: Combine data from multiple collections into one..how?
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Doing unions in MongoDB in a 'SQL UNION' fashion is possible using aggregations along with lookups, in a single query. Here is an example I have tested that works with MongoDB 4.0:
// Create employees data for testing the union.
d...
How to find a text inside SQL Server procedures / triggers?
... find text....
DECLARE @Search varchar(255)
SET @Search='[10.10.100.50]'
SELECT DISTINCT
o.name AS Object_Name,o.type_desc
FROM sys.sql_modules m
INNER JOIN sys.objects o ON m.object_id=o.object_id
WHERE m.definition Like '%'+@Search+'%'
ORDER BY 2,1
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How to define “type disjunction” (union types)?
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Miles Sabin describes a very nice way to get union type in his recent blog post Unboxed union types in Scala via the Curry-Howard isomorphism:
He first defines negation of types as
type ¬[A] = A => Nothing
using De Morgan's law this allows him to define union ty...
Intersection and union of ArrayLists in Java
... Test().intersection(list1, list2));
System.out.println(new Test().union(list1, list2));
}
public <T> List<T> union(List<T> list1, List<T> list2) {
Set<T> set = new HashSet<T>();
set.addAll(list1);
set.addAll(list2);
...
What is the strict aliasing rule?
...mited buffer doesn't necessarily help.
So how do I get around this?
Use a union. Most compilers support this without complaining about strict aliasing. This is allowed in C99 and explicitly allowed in C11.
union {
Msg msg;
unsigned int asBuffer[sizeof(Msg)/sizeof(unsigned int)];
};
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What's the difference between INNER JOIN, LEFT JOIN, RIGHT JOIN and FULL JOIN? [duplicate]
...These pictures don't do it for me. Why is the top right picture not simply SELECT * FROM TableA;? Why is the top left picture not simply SELECT * FROM TableB;? Why is the top middle picture not SELECT * FROM A INTERSECT SELECT * FROM B ? etc
– onedaywhen
Sep 9 ...
Why do we need C Unions?
When should unions be used? Why do we need them?
18 Answers
18
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Is there a Max function in SQL Server that takes two values like Math.Max in .NET?
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return isnull(@val2,@val1)
end
... and you would call it like so ...
SELECT o.OrderId, dbo.InlineMax(o.NegotiatedPrice, o.SuggestedPrice)
FROM Order o
share
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improve this answer
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Optimal way to concatenate/aggregate strings
...Transact SQL, which should work fine in Azure.
;WITH Partitioned AS
(
SELECT
ID,
Name,
ROW_NUMBER() OVER (PARTITION BY ID ORDER BY Name) AS NameNumber,
COUNT(*) OVER (PARTITION BY ID) AS NameCount
FROM dbo.SourceTable
),
Concatenated AS
(
SELECT
...
How to output MySQL query results in CSV format?
...ech-recipes.com/rx/1475/save-mysql-query-results-into-a-text-or-csv-file/
SELECT order_id,product_name,qty
FROM orders
WHERE foo = 'bar'
INTO OUTFILE '/var/lib/mysql-files/orders.csv'
FIELDS TERMINATED BY ','
ENCLOSED BY '"'
LINES TERMINATED BY '\n';
Using this command columns names will not be e...