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Finding the type of an object in C++
...
dynamic_cast should do the trick
TYPE& dynamic_cast<TYPE&> (object);
TYPE* dynamic_cast<TYPE*> (object);
The dynamic_cast keyword casts a datum from one pointer or reference type to another, performing a runtime ...
Base64 encoding in SQL Server 2005 T-SQL
...-- Encode the string "TestData" in Base64 to get "VGVzdERhdGE="
SELECT
CAST(N'' AS XML).value(
'xs:base64Binary(xs:hexBinary(sql:column("bin")))'
, 'VARCHAR(MAX)'
) Base64Encoding
FROM (
SELECT CAST('TestData' AS VARBINARY(MAX)) AS bin
) AS bin_sql_server_temp;
-- De...
What is the difference between up-casting and down-casting with respect to class variable
What is the difference between up-casting and down-casting with respect to class variable?
10 Answers
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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...
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...
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...
Downcasting in Java
Upcasting is allowed in Java, however downcasting gives a compile error.
11 Answers
1...
Any idea why I need to cast an integer literal to (int) here?
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The compiler tries to subtract 128 from (Integer) instead of casting -128 to Integer. Add () to fix it
Integer i3 = (Integer) -128; // doesn't compile
Integer i3 = (Integer) (-128); // compiles
According to BoltClock in the comments the cast to int works as intended, because it is ...
Safely casting long to int in Java
What's the most idiomatic way in Java to verify that a cast from long to int does not lose any information?
10 Answers
...
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...