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What's the difference between INNER JOIN, LEFT JOIN, RIGHT JOIN and FULL JOIN? [duplicate]
...have a problem with the whole concept: those are visual representations of union, intersect, except, etc. They have no visual representation of projection therefore cannot be joins. I think it will confuse more than benefit when the context is joins.
– onedaywhen
...
Multi-statement Table Valued Function vs Inline Table Valued Function
... you pass as a "Company Number". Normally, you could create a view with a union all then filter by company number but I found that sometimes sql server pulls back the entire union and is not smart enough to call the one select. A table function can have logic to choose the source.
...
Generate a Hash from string in Javascript
...ring.hashCode function taken from Java. It is ancient (from Gosling Emacs, 1981), extremely weak, and performance-wise, it makes zero sense in modern JavaScript. In fact, hashCode is significantly faster by using ES6 Math.imul, but no one took notice. We can achieve significantly better hash functio...
How do I get SUM function in MySQL to return '0' if no values are found?
...as expected_sum,
COALESCE(SUM(val), 0) as actual_sum
FROM foo
UNION ALL
SELECT 'bar' as table_name,
'all non-null' as description,
21 as expected_sum,
COALESCE(SUM(val), 0) as actual_sum
FROM bar
UNION ALL
S...
Type definition in object literal in TypeScript
...ally need a type that you can be lazily initialized: Mark it is a nullable union type (null or Type). The type system will prevent you from using it without first ensuring it has a value.
In tsconfig.json, make sure you enable strict null checks:
"strictNullChecks": true
Then use this pattern an...
TypeScript function overloading
... TypeScript 1.4, you can typically remove the need for an overload using a union type. The above example can be better expressed using:
myMethod(a: string | number, b?: string) {
alert(a.toString());
}
The type of a is "either string or number".
...
Why was the switch statement designed to need a break?
...
2. Antipatterns: Doesn't provide "clean" tagged unions, one of the two fundamental data-representation idioms of assembly. (Knuth, vol 1, ch 2) Instead, "untagged unions," a non-idiomatic hack. This choice has hobbled the way people think of data for decades. And NUL-termi...
What are the differences between struct and class in C++?
...ate by
default. Members of a class defined
with the keywords struct or union
are public by default.
Additional difference: the keyword class can be used to declare template parameters, while the struct keyword cannot be so used.
...
How do I split a string so I can access item x?
... 1,
charindex(@separator, @str)
union all
select
p + 1,
b + 1,
charindex(@separator, @str, b + 1)
from tokens
where b > 0
)
select
p-1 zeroB...
Select values from XML field in SQL Server 2008
...tName><lastName>Johnson</lastName></person>' xmlField
union select '<person><firstName>Kathy</firstName><lastName>Carter</lastName></person>'
union select '<person><firstName>Bob</firstName><lastName>Burns</lastName&...