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How to select rows with no matching entry in another table?
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Here's a simple query:
SELECT t1.ID
FROM Table1 t1
LEFT JOIN Table2 t2 ON t1.ID = t2.ID
WHERE t2.ID IS NULL
The key points are:
LEFT JOIN is used; this will return ALL rows from Table1, regardless of whether or not there is a matching row i...
How to set timeout on python's socket recv method?
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The typical approach is to use select() to wait until data is available or until the timeout occurs. Only call recv() when data is actually available. To be safe, we also set the socket to non-blocking mode to guarantee that recv() will never block indef...
TCP vs UDP on video stream
...s clients is long due to the singularity of the event. Pre-recorded video-casts typically don't have as much of a problem with this because viewers stagger their replay activity; therefore TCP is more appropriate for replaying a video-on-demand.
IP multicast significantly reduces video bandwidth re...
Table name as variable
...mpare data between the same tables of different databases:
static query:
SELECT * FROM [DB_ONE].[dbo].[ACTY]
EXCEPT
SELECT * FROM [DB_TWO].[dbo].[ACTY]
since I want easily change tha name of table and schema I have created this dynamic query:
declare @schema varchar(50)
declare @table varchar(5...
xcode-select active developer directory error
...red node-gyp ... but could be triggered by anything which requires xcode-select .
23 Answers
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Sublime Text 2 multiple line edit
...t and edit all lines at once.
It's also called "Split into Lines" in the "Selection" menu.
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Unioning two tables with different number of columns
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Add extra columns as null for the table having less columns like
Select Col1, Col2, Col3, Col4, Col5 from Table1
Union
Select Col1, Col2, Col3, Null as Col4, Null as Col5 from Table2
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jQuery get value of selected radio button
The problem statement is simple. I need to see if user has selected a radio button from a radio group. Every radio button in the group share same id.
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Why do C++ libraries and frameworks never use smart pointers?
... to be readonly you can use a const reference (you can still do some nasty casts to be able to write the object) but you get the maximum of protection possible (it's the same with smart pointers).
But I do agree that it's much nicer to just return the object.
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UITextView style is being reset after setting text property
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Sitting with this for hours, I found the bug.
If the property "Selectable" = NO it will reset the font and fontcolor when setText is used.
So turn Selectable ON and the bug is gone.
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