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Pad a string with leading zeros so it's 3 characters long in SQL Server 2008
...
If the field is already a string, this will work
SELECT RIGHT('000'+ISNULL(field,''),3)
If you want nulls to show as '000'
It might be an integer -- then you would want
SELECT RIGHT('000'+CAST(field AS VARCHAR(3)),3)
As required by the question this answer only w...
Store select query's output in one array in postgres
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There are two ways. One is to aggregate:
SELECT array_agg(column_name::TEXT)
FROM information.schema.columns
WHERE table_name = 'aean'
The other is to use an array constructor:
SELECT ARRAY(
SELECT column_name
FROM information.schema.columns
WHERE table_name = ...
What does = +_ mean in JavaScript
...
r = +_;
+ tries to cast whatever _ is to a number.
_ is only a variable name (not an operator), it could be a, foo etc.
Example:
+"1"
cast "1" to pure number 1.
var _ = "1";
var r = +_;
r is now 1, not "1".
Moreover, according to the M...
C++ equivalent of java's instanceof
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Try using:
if(NewType* v = dynamic_cast<NewType*>(old)) {
// old was safely casted to NewType
v->doSomething();
}
This requires your compiler to have rtti support enabled.
EDIT:
I've had some good comments on this answer!
Every time you need...
Why unsigned integer is not available in PostgreSQL?
...< 65536);
Here is what psql gives when I try to abuse the type.
DS1=# select (346346 :: uint2);
ERROR: value for domain uint2 violates check constraint "uint2_check"
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What is uintptr_t data type
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Another common use case of casting a pointer to an int is to create an opaque handle that hides the pointer. This is useful for returning a reference to an object from APIs where you want to keep the object private to the library and prevent applicati...
Get int value from enum in C#
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Just cast the enum, e.g.
int something = (int) Question.Role;
The above will work for the vast majority of enums you see in the wild, as the default underlying type for an enum is int.
However, as cecilphillip points out, enum...
What is an “unwrapped value” in Swift?
...gift:getGift())
//Now we have to unwrap f00, unwrap its entry, then force cast it into the type we hope it is, and then repeat this in nested fashion until we get to the final value.
var b4r = (((((((((((f00![10]! as! [Int:Any?])[9]! as! [Int:Any?])[8]! as! [Int:Any?])[7]! as! [Int:Any?])[6]! as! ...
Sorting an IList in C#
...rty, I believe you could sort as follows:
from c in list
orderby c.Engine
select c;
Edit: You do need to be quick to get answers in here. As I presented a slightly different syntax to the other answers, I will leave my answer - however, the other answers presented are equally valid.
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What is a void pointer in C++? [duplicate]
... it stores which kinds of objects, and therefore which type you can safely cast it to.
This construct is nothing like dynamic or object in C#. Those tools actually know what the original type is; void* does not. This makes it far more dangerous than any of those, because it is very easy to get it ...