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In Postgresql, force unique on combination of two columns
...l1, col2)
)
autoincrement is not postgresql. You want a serial.
If col1 and col2 make a unique and can't be null then they make a good primary key:
CREATE TABLE someTable (
col1 int NOT NULL,
col2 int NOT NULL,
primary key (col1, col2)
)
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Measuring elapsed time with the Time module
... You can also take a look at profilehooks pip install profilehooks, and its homepage here
– pjama
Jan 5 '13 at 5:08
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How to pass parameters to anonymous class?
...se are executed in the same order as field assignments, i.e. after super() and before the rest of the actual constructor. new someclass(){ fields; {initializer} fields; methods(){} }. It's sort of like a static initializer but without the static keyword. docs.oracle.com/javase/specs/jls/se7/html/jls...
Count number of days between two dates
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With the Date (and DateTime) classes you can do (end_date - start_date).to_i to get the number of days difference.
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Email address validation using ASP.NET MVC data type attributes
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Thank you @Shittu Olugbenga! But I can't understand why this doesn't work: [DataType(DataType.EmailAddress, ErrorMessage = "Error message.")]
– Wellington Zanelli
Sep 18 '14 at 12:34
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Installing PIL with pip
I am trying to install PIL (the Python Imaging Library) using the command:
21 Answers
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How to extract a string using JavaScript Regex?
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You need to use the m flag:
multiline; treat beginning and end characters (^ and $) as working
over multiple lines (i.e., match the beginning or end of each line
(delimited by \n or \r), not only the very beginning or end of the
whole input string)
Also put the * in the r...
Performance - Date.now() vs Date.getTime()
.../date it's been set to). That is, if you do this:
var now = new Date();
and then wait a while, a subsequent call to now.getTime() will tell the time at the point the variable was set.
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How to encode URL parameters?
...swered May 11 '18 at 9:01
Kyle VanderBeekKyle VanderBeek
74777 silver badges77 bronze badges
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How can I switch my signed in user in Visual Studio 2013?
...e of Visual Studio 2013 is the ability to sign in with a Microsoft Account and have your settings be persisted across all of your instances of Visual Studio, amongst other things.
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