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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
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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...
No Exception while type casting with a null in java
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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 to check SQL Server version
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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...