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Importance of varchar length in MySQL table
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Anytime your select query uses a temporary table (group and order by operations, among other things) it will convert varchar(200) to a char(200) and performance will suffer.
– Jamie
Feb 7 '13 at 20:1...
How does database indexing work? [closed]
...arising from the file systems size limits, careful thought must be used to select the correct fields to index.
Since indices are only used to speed up the searching for a matching field within the records, it stands to reason that indexing fields used only for output would be simply a waste of disk...
ValidateRequest=“false” doesn't work in Asp.Net 4
...r. Maintains security and is extremely flexible since you can use it on a selective basis.
– cmartin
Jun 5 '15 at 18:38
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Remove unwanted parts from strings in a column
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A very simple method would be to use the extract method to select all the digits. Simply supply it the regular expression '\d+' which extracts any number of digits.
df['result'] = df.result.str.extract(r'(\d+)', expand=True).astype(int)
df
time result
1 09:00 52
2 10:00...
WAMP/XAMPP is responding very slow over localhost
...\Services\TCPIP6\Parameters
Right click on Parameters, expand New, and select DWORD (32-bit) Value
Enter DisabledComponents into the Name field
Double click on the new DisabledComponents value, enter ffffffff into the Value data dialog box, and click the OK button
Confirm the new regist...
How to get current user, and how to use User class in MVC5?
...{
uid = context.Users.Where(x => x.UserName == userName).Select(x=>x.Id).FirstOrDefault();
return uid;
}
return uid;
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How to cancel an $http request in AngularJS?
...ked for me - very simple and i added another one to name the call so i can select the call and only cancel some of the calls
– Simon Dragsbæk
Nov 16 '15 at 12:57
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android View not attached to window manager
...using Eclipse. Right click in the margin just to the left of your code and select "Toggle breakpoint". You then need to run your application in debug mode, the button that looks like a green insect next to the normal run button. When the program hits a breakpoint, Eclipse will switch to the debug pe...
IEnumerable to string [duplicate]
...urer sequence, rather than a cast. Something like Enumerable.Range(65, 26).Select(i => (char)i);, this should avoid the chance for an optimized shortcut.
– Jodrell
Oct 28 '13 at 9:39
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What is AssemblyInfo.cs used for?
...mblyInfo.cs.
In Windows Explorer, right click your project's .exe output, select Properties, and go to the Details tab. That is the information generated by AssemblyInfo.cs.
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