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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...
Integer division: How do you produce a double?
...
double num = 5;
That avoids a cast. But you'll find that the cast conversions are well-defined. You don't have to guess, just check the JLS. int to double is a widening conversion. From §5.1.2:
Widening primitive conversions do not
lose informa...
Cast int to varchar
I have below query and need to cast id to varchar
8 Answers
8
...
Get the week start date and week end date from week number
...f-week value. Here is an example:
WITH TestData(SomeDate) AS (
SELECT CAST('20001225' AS DATETIME) UNION ALL
SELECT CAST('20001226' AS DATETIME) UNION ALL
SELECT CAST('20001227' AS DATETIME) UNION ALL
SELECT CAST('20001228' AS DATETIME) UNION ALL
SELECT CAST('20001229' AS DATETI...
Best approach to remove time part of datetime in SQL Server
...w etc by changing "0" base
Edit, Oct 2011
For SQL Server 2008+, you can CAST to date i.e. CAST(getdate() AS date). Or just use date datatype so no time to remove.
Edit, Jan 2012
A worked example of how flexible this is: Need to calculate by rounded time or date figure in sql server
Edit, May 2...
How to cast List to List
...
you can always cast any object to any type by up-casting it to Object first. in your case:
(List<Customer>)(Object)list;
you must be sure that at runtime the list contains nothing but Customer objects.
Critics say that such cast...
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...
How can I reliably get an object's address when operator& is overloaded?
...f_impl
{
static inline T * f( T & v, long ) {
return reinterpret_cast<T*>(
&const_cast<char&>(reinterpret_cast<const volatile char &>(v)));
}
static inline T * f( T * v, int ) { return v; }
};
template<class T>
T * addressof( T & v ) {
...
Why should casting be avoided? [closed]
I generally avoid casting types as much as possible since I am under the impression that it's poor coding practice and may incur a performance penalty.
...
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...