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What are the use cases for selecting CHAR over VARCHAR in SQL?
...mption that char uses less processing power than varchar may be true...for now...but database engines get better over time and this sort of general rule has the making of a future "myth".
Another thing: I have never seen a performance problem because someone decided to go with varchar. You will ma...
How to select rows that have current day's timestamp?
...sert about 7k rows
('2013-02-08 20:01:12') ;
Lets try the 2 versions now.
Version 1 with DATE(timestamp) = ?
EXPLAIN
SELECT * FROM test
WHERE DATE(timestamp) = CURDATE() --- using DATE(timestamp)
ORDER BY timestamp ;
Explain:
ID SELECT_TYPE TABLE TYPE POSSIBLE_KEYS KEY...
How to capture the browser window close event?
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@Jonny: It's now just .on().
– SLaks
Dec 26 '17 at 18:14
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Change computer name for a TFS Workspace
...stem Administrator renamed my computer. So where it was "MyLaptop2" it is now just "MyLaptop".
15 Answers
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How do you force a CIFS connection to unmount
... the internet connection is down, and anything that touches the CIFS mount now takes several minutes to timeout, and is unkillable while you wait. I can't even run ls in my home directory because there is a symlink pointing inside the CIFS mount and ls tries to follow it to decide what color it sho...
How to make URL/Phone-clickable UILabel?
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Setting the font is now done by: button.titleLabel.font = [UIFont systemFontOfSize:size];
– Leon
Apr 16 '18 at 8:12
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How do I programmatically force an onchange event on an input?
... This is how to do it properly, natively. Supported in all browsers now: caniuse.com/#feat=dispatchevent
– Willem Mulder
Aug 25 '16 at 10:38
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iPhone SDK: what is the difference between loadView and viewDidLoad?
...self.view, then releasing...it seemed somehow awkward, unnecessary. I can now understand why that decision would have led me down the path where I now find myself.
– ryan.scott
Feb 23 '09 at 4:29
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What does an exclamation mark mean in the Swift language?
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OK. So the docs talk about using ! when you know for sure it can be unwrapped. But you can run the code fine without it (a forth option for your list - implicit unwrapping) AND without checking first. You get back the value or nil if nil. But if you know for sure that ...
Fastest way to determine if record exists
...I'm not sure if an Index exists on this field, and my newbish SQL doesn't know how to find out. I am working with this DB from Java via JDBC and the database is remotely located in a colo somewhere. I've only been provided a "database summary" which just details which fields exist in each table, the...