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Can you have if-then-else logic in SQL? [duplicate]
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The CASE statement is the closest to an IF statement in SQL, and is supported on all versions of SQL Server:
SELECT CASE <variable>
WHEN <value> THEN <returnvalue>
WHEN <othervalue> THEN <returnthis>
ELSE <retur...
Table Naming Dilemma: Singular vs. Plural Names [closed]
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Others have given pretty good answers as far as "standards" go, but I just wanted to add this... Is it possible that "User" (or "Users") is not actually a full description of the data held in the table? Not that you should get too crazy with table names and specificity, but p...
“open/close” SqlConnection or keep open?
...d Dec 14 '10 at 13:02
Adriaan StanderAdriaan Stander
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What's the difference between findAndModify and update in MongoDB?
I'm a little bit confused by the findAndModify method in MongoDB. What's the advantage of it over the update method? For me, it seems that it just returns the item first and then updates it. But why do I need to return the item first? I read the MongoDB: the definitive guide and it says that i...
iOS5 Storyboard error: Storyboards are unavailable on iOS 4.3 and prior
I've built a small app using storyboards and it ran great. Just before final testing I decided to try it out to see if it runs on iOS 4.3. I clicked on the gray 5.0 in the project settings and selected 4.3.
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How to set Python's default version to 3.x on OS X?
I'm running Mountain Lion and the basic default Python version is 2.7. I downloaded Python 3.3 and want to set it as default.
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MySQL Error 1215: Cannot add foreign key constraint
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I'm guessing that Clients.Case_Number and/or Staff.Emp_ID are not exactly the same data type as Clients_has_Staff.Clients_Case_Number and Clients_has_Staff.Staff_Emp_ID.
Perhaps the columns in the parent tables are INT UNSIGNED?
They need to be exactly the same...
Find running median from a stream of integers
...n left side to represent elements that are less than the effective median, and a min heap on right side to represent elements that are greater than the effective median.
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“x not in y” or “not x in y”
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They always give the same result.
In fact, not 'ham' in 'spam and eggs' appears to be special cased to perform a single "not in" operation, rather than an "in" operation and then negating the result:
>>> import dis
>>> def notin():
'ham' not in 'spam and eggs'
&g...
SQL statement to select all rows from previous day
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WHERE YourDate >= dateadd(day,datediff(day,1,GETDATE()),0)
AND YourDate < dateadd(day,datediff(day,0,GETDATE()),0)
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