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Why does PostgreSQL perform sequential scan on indexed column?
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If the SELECT returns more than approximately 5-10% of all rows in the table, a sequential scan is much faster than an index scan.
This is because an index scan requires several IO operations for each row (look up the row in the ...
No connection could be made because the target machine actively refused it?
...ameter is often configurable if you control the server, and is likely read from some settings file or the registry. Investigate how to configure your server.
If you wrote the server, you might have heavy processing in the accept of your socket, and this can be better moved to a separate worker-thr...
Horizontal ListView in Android?
...he ListView horizontally? I have done this using a gallery view, but the selected item comes to the center of the screen automatically. I don't want the selected item at the same spot I clicked. How can I rectify this problem? My idea was to set the ListView with a horizontal scroll. Share your ...
How do I shutdown, restart, or log off Windows via a bat file?
...l options:
-f — Forces programs to exit. Prevents the shutdown process from getting stuck.
-t <seconds> — Sets the time until shutdown. Use -t 0 to shutdown immediately.
-c <message> — Adds a shutdown message. The message will end up in the Event Log.
-y — Forces a "yes" answer...
Hidden Features of Visual Studio (2005-2010)?
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Make a selection with ALT pressed - selects a square of text instead of whole lines.
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answered Sep 19 ...
DropDownList's SelectedIndexChanged event not firing
I have a DropDownList object in my web page. When I click on it and select a different value, nothing happens, even though I have a function wired up to the SelectedIndexChanged event.
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update columns values with column of another table based on condition [duplicate]
...ble1.id = table2.id
You can also try this:
UPDATE table1
SET price=(SELECT price FROM table2 WHERE table1.id=table2.id);
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How to change Vagrant 'default' machine name?
Where does the name 'default' come from when launching a vagrant box?
7 Answers
7
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How can I convert uppercase letters to lowercase in Notepad++
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Just select the text you want to change, right click and select UPPERCASE or lowercase depending on what you want.
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When should I use a table variable vs temporary table in sql server?
... source for the data inserted to the table is from a potentially expensive SELECT statement then consider that using a table variable will block the possibility of this using a parallel plan.
If you need the data in the table to survive a rollback of an outer user transaction then use a table variab...