大约有 2,600 项符合查询结果（耗时：0.0144秒） [XML]
How to check if a table exists in a given schema
... dba.SE discussing "Information schema vs. system catalogs"
Alternative: cast to regclass
SELECT 'schema_name.table_name'::regclass
This raises an exception if the (optionally schema-qualified) table (or other object occupying that name) does not exist.
If you do not schema-qualify the table n...
Can we define implicit conversions of enums in c#?
...'t need to use an enum just for the sake of it. You either put an explicit cast or just write a static class with const ints.
– Trap
Feb 8 '14 at 0:56
3
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How do I perform an IF…THEN in an SQL SELECT?
...osest to IF in SQL and is supported on all versions of SQL Server.
SELECT CAST(
CASE
WHEN Obsolete = 'N' or InStock = 'Y'
THEN 1
ELSE 0
END AS bit) as Saleable, *
FROM Product
You only need to do the CAST if you wa...
Checking for a null int value from a Java ResultSet
...ying to test for a null value, from a ResultSet, where the column is being cast to a primitive int type.
10 Answers
...
Cocoa Touch: How To Change UIView's Border Color And Thickness?
...as You say. r, g and b can be int, as C (and objC IS C) promotions will cast int r=128 to double when making: r/255.0. By the way You got double, and Clang will cast to CGFloat.
– ingconti
Jan 28 '18 at 14:54
...
How to convert a Django QuerySet to a list
...
Be careful with this. When you cast this to a a list the distinct flag may become disregarded.
– rh0dium
Oct 1 '15 at 19:52
...
Why should I use a pointer rather than the object itself?
...back(&triangle);
for (auto& e : vector)
{
auto test = dynamic_cast<Triangle*>(e); // I only care about triangles
if (!test) // not a triangle
e.GenericFunction();
else
e.TriangleOnlyMagic();
}
So say if only Triangles had a Rotate function, it would be ...
How to call erase with a reverse iterator
...This code works, but please explain why next is used and how is it safe to cast a forward iterator to a reverse iterator without the world collapsing
– Lefteris E
Mar 23 at 12:13
1...
php - get numeric index of associative array
...a)));
You will always get 0, which is wrong, so the solution would be to cast the index (if you use a variable) to a string like this:
$ind = 0;
echo array_search((string)$ind, array_map("strval", array_keys($a)));
share...
Nested using statements in C#
... Well they are all the same type if they are all IDisposable perhaps a cast would work?
– jpierson
Jan 17 '12 at 17:43
8
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