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MySQL - Make an existing Field Unique
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ALTER IGNORE TABLE mytbl ADD UNIQUE (columnName);
For MySQL 5.7.4 or later:
ALTER TABLE mytbl ADD UNIQUE (columnName);
As of MySQL 5.7.4, the IGNORE clause for ALTER TABLE is removed and
its use produces an error.
So, make sure to remove duplicate entries first as IGNORE key...
How to convert a number to string and vice versa in C++
...the following functions are present in <string> (as per paragraph 21.5).
string to numeric
float stof(const string& str, size_t *idx = 0);
double stod(const string& str, size_t *idx = 0);
long double stold(const string& str, size_t *idx = 0);
int ...
How to set Default Controller in asp.net MVC 4 & MVC 5
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Imad Alazani
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answered Jan 20 '13 at 16:30
Dave AlperovichDave A...
Else clause on Python while statement
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answered Jul 21 '10 at 2:51
arsars
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What's the best way to communicate between view controllers?
...p.
– Kevin Elliott
Jan 10 '10 at 0:05
What if you also wish to use BookPickerController for picking a book for a wish ...
Multiple INSERT statements vs. single INSERT with multiple VALUES
...et the average compile time per clause. The results are below
Up until 250 VALUES clauses present the compile time / number of clauses has a slight upward trend but nothing too dramatic.
But then there is a sudden change.
That section of the data is shown below.
+------+----------------+---...
How does Go update third-party packages?
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StartupGuy
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answered Apr 30 '12 at 12:33
tux21btux21b
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How to programmatically display version/build number of target in iOS app?
...naryKey("CFBundleShortVersionString") as! String
Swift 3.0+ (tested with 5.0):
let appVersionString: String = Bundle.main.object(forInfoDictionaryKey: "CFBundleShortVersionString") as! String
To get the build number:
Objective-C:
NSString * appBuildString = [[NSBundle mainBundle] objectForInf...
Comparing Haskell's Snap and Yesod web frameworks
...deal.
– Dan Burton
Apr 13 '11 at 19:57
2
Yesod also has an as-yet-unreleased interface to mongodb...
grep a file, but show several surrounding lines?
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answered Aug 12 '08 at 17:57
Pat NotzPat Notz
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