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Shorter syntax for casting from a List to a List?
I know its possible to cast a list of items from one type to another (given that your object has a public static explicit operator method to do the casting) one at a time as follows:
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Difference between two dates in MySQL
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SELECT TIMEDIFF('2007-12-31 10:02:00','2007-12-30 12:01:01');
-- result: 22:00:59, the difference in HH:MM:SS format
SELECT TIMESTAMPDIFF(SECOND,'2007-12-30 12:01:01','2007-12-31 10:02:00');
-- result: 79259 the differenc...
How to make a query with group_concat in sql server [duplicate]
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Query:
SELECT
m.maskid
, m.maskname
, m.schoolid
, s.schoolname
, maskdetail = STUFF((
SELECT ',' + md.maskdetail
FROM dbo.maskdetails md
WHERE m.maskid = md.maskid
FOR X...
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.
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How can I post an array of string to ASP.NET MVC Controller without a form?
...C and JQuery, and one of the pages is a list of items in which some can be selected. Then I would like to press a button and send a List (or something equivalent) to my controller containing the ids of the items that were selected, using JQuery's Post function.
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Object-orientation in C
...ject at runtime! You just reassign it a new vtable pointer. You can even selectively change some of the virtual functions while keeping others, creating new hybrid types. Just be careful to create a new vtable instead of modifying the global vtable, otherwise you'll accidentally affect all object...
Get list of databases from SQL Server
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Execute:
SELECT name FROM master.sys.databases
This the preferred approach now, rather than dbo.sysdatabases, which has been deprecated for some time.
Execute this query:
SELECT name FROM master.dbo.sysdatabases
or if you pref...
When to use Cast() and Oftype() in Linq
I am aware of two methods of casting types to IEnumerable from an Arraylist in Linq and wondering in which cases to use them?
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How to cast int to enum in C++?
How do I cast an int to an enum in C++?
5 Answers
5
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Is there a Boolean data type in Microsoft SQL Server like there is in MySQL? [duplicate]
...compared using a comparison operator such as =, <> or IS NULL. e.g.
SELECT
a.answer_body
FROM answers AS a
WHERE a.is_accepted = 0;
From a formatting perspective, a bit value is typically displayed as 0 or 1 in client software. When a more user-friendly format is required, and it can't ...