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Union Vs Concat in Linq
...mpare references of items. Your items have different references, thus they all are considered different. When you cast to base type X, reference is not changed.
If you will override Equals and GetHashCode (used to select distinct items), then items will not be compared by reference:
class X
{
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Closing Database Connections in Java
...u are done with using your Connection, you need to explicitly close it by calling its close() method in order to release any other database resources (cursors, handles, etc) the connection may be holding on to.
Actually, the safe pattern in Java is to close your ResultSet, Statement, and Connectio...
Update a record without first querying?
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@Gabriel Won't this update all properties though? What if I only want to modify a single one?
– David Pfeffer
Aug 15 '12 at 0:45
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Clear Application's Data Programmatically
I want to clear my application's data programmatically.
6 Answers
6
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C# how to create a Guid value?
...uid();
Hey, its a 'valid', although not very useful, Guid.
(the guid is all zeros, if you don't know. Sometimes this is needed to indicate no guid, in cases where you don't want to use a nullable Guid)
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Install gitk on Mac
Does anyone know how to install gitk on Mac?
13 Answers
13
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JOIN two SELECT statement results
...COUNT(*) AS '# Late' FROM Table WHERE Age > Palt GROUP BY ks
Or UNION ALL if you want duplicates:
SELECT ks, COUNT(*) AS '# Tasks' FROM Table GROUP BY ks
UNION ALL
SELECT ks, COUNT(*) AS '# Late' FROM Table WHERE Age > Palt GROUP BY ks
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Undo git mv (rename)
...git mv file2 file1
Updates the index for both old and new paths automatically.
Check documentation of git mv
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Mac SQLite editor [closed]
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Unless I'm missing something, it doesn't allow you to alter existing tables.
– mahdaeng
Dec 12 '11 at 20:54
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Visual Studio appears to randomly adopt American keyboard layout
Gah! This is really causing me hassle today. Suddenly without warning '@' (at symbol) and '"' (double quote) are trading places on my keyboard but ONLY in Visual Studio 2008!
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