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How do I cast a string to integer and have 0 in case of error in the cast with PostgreSQL?
...conditionals, so you shouldn't get any non-integers hitting your ::integer cast. It also handles NULL values (they won't match the regexp).
If you want zeros instead of not selecting, then a CASE statement should work:
SELECT CASE WHEN myfield~E'^\\d+$' THEN myfield::integer ELSE 0 END FROM mytabl...
How to store arrays in MySQL?
... AS pfs_person_name,
cast(concat('[', group_concat(json_quote(fruit_name) ORDER BY fruit_name SEPARATOR ','), ']') as json) AS pfs_fruit_name_array
FROM
person
INNER JOIN person_fruit
ON person.person_id = person_fruit.pf_person
...
TypeScript: casting HTMLElement
Does anyone know how to cast in TypeScript?
13 Answers
13
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No Exception while type casting with a null in java
...
You can cast null to any reference type without getting any exception.
The println method does not throw null pointer because it first checks whether the object is null or not. If null then it simply prints the string "null". Otherw...
How can I truncate a datetime in SQL Server?
...odern versions of Sql Server. For Sql Server 2008 and later, it's simple:
cast(getDate() As Date)
Note that the last three paragraphs near the bottom still apply, and you often need to take a step back and find a way to avoid the cast in the first place.
But there are other ways to accomplish th...
error: cannot dynamic_cast ‘b’ (of type ‘class Base*’) to type ‘c...
error: cannot dynamic_cast ‘b’ (of type ‘class Base*’) to type ‘class Derived*’ (source type is not polymorphic)在将父类型转换为子类型时,可以使用static_cast和dynamic_cast.如果使用dynamic_cast,它要求父类必须为多态的,即要求至少有一个虚函数,因此....
How to check SQL Server version
...
declare @sqlVers numeric(4,2)
select @sqlVers = left(cast(serverproperty('productversion') as varchar), 4)
Gives 8.00, 9.00, 10.00 and 10.50 for SQL 2000, 2005, 2008 and 2008R2 respectively.
Also, Try the system extended procedure xp_msver. You can call this stored procedure...
C++ convert hex string to signed integer
...gt;> x;
// output it as a signed type
std::cout << static_cast<int>(x) << std::endl;
}
In the new C++11 standard, there are a few new utility functions which you can make use of! specifically, there is a family of "string to number" functions (http://en.cppreference.co...
Cast from VARCHAR to INT - MySQL
...
As described in Cast Functions and Operators:
The type for the result can be one of the following values:
BINARY[(N)]
CHAR[(N)]
DATE
DATETIME
DECIMAL[(M[,D])]
SIGNED [INTEGER]
TIME
UNSIGNED [INTEGER]
Therefore,...
How expensive is RTTI?
...me if you can afford to do
if (typeid(a) == typeid(b)) {
B* ba = static_cast<B*>(&a);
etc;
}
instead of
B* ba = dynamic_cast<B*>(&a);
if (ba) {
etc;
}
The former involves only one comparison of std::type_info; the latter necessarily involves traversing an inheritance...